Metal-ligand complex catalyzed processes

ABSTRACT

This invention relates to a process which comprises reacting one or more reactants in the presence of a metal-organopolyphosphite ligand complex catalyst to produce a reaction product fluid comprising one or more products, wherein said process is conducted at a free organopolyphosphite ligand concentration sufficient to prevent and/or lessen hydrolytic degradation of the organopolyphosphite ligand and deactivation of the metal-organopolyphosphite ligand complex catalyst.

This application claims the benefit of provisional U.S. patentapplication Ser. Nos. 60/008289, 60/008763, 60/008284 and 60/008286, allfiled Dec. 6, 1995, and all of which are incorporated herein byreference.

BRIEF SUMMARY OF THE INVENTION

1. Technical Field

This invention relates to improved metal-organopolyphosphite ligandcomplex catalyzed processes. More particularly this invention relates tothe use of free organopolyphosphite ligand at low organopolyphosphiteligand to metal ratios to prevent and/or lessen hydrolytic degradationof the organopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst of such processes.

2. Background of the Invention

It is known in the art that various products may be produced by reactingone or more reactants in the presence of an metal-organopolyphosphiteligand complex catalyst. However, stabilization of the catalyst andorganopolyphosphite ligand remains a primary concern of the art.Obviously catalyst stability is a key issue in the employment of anycatalyst. Loss of catalyst or catalytic activity due to undesirablereactions of the highly expensive metal catalysts can be detrimental tothe production of the desired product. Likewise degradation of theorganophosphite ligand employed during the process can lead to poisoningorganophosphite compounds or inhibitors or acidic byproducts that canlower the catalytic activity of the metal catalyst. Moreover, productioncosts of the product obviously increase when productivity of thecatalyst decreases.

For instance, a major cause of organophosphite ligand degradation andcatalyst deactivation of metal-organophosphite ligand complex catalyzedhydroformylation processes is due to the hydrolytic instability of theorganophosphite ligands. All organophosphites are susceptible tohydrolysis in one degree or another, the rate of hydrolysis oforganophosphites in general being dependent on the stereochemical natureof the organophosphite. In general, the bulkier the steric environmentaround the phosphorus atom, the slower the hydrolysis rate. For example,tertiary triorganophosphites such as triphenylphosphite are moresusceptible to hydrolysis than diorganophosphites, such as disclosed inU.S. Pat. No. 4,737,588, and organopolyphosphites such as disclosed inU.S. Pat. Nos. 4,748,261 and 4,769,498. Moreover, all such hydrolysisreactions invariably produce phosphorus acidic compounds which catalyzethe hydrolysis reactions. For example, the hydrolysis of a tertiaryorganophosphite produces a phosphonic acid diester, which ishydrolyzable to a phosphonic acid monoester, which in turn ishydrolyzable to H₃ PO₃ acid. Moreover, hydrolysis of the ancillaryproducts of side reactions, such as between a phosphonic acid diesterand the aldehyde or between certain organophosphite ligands and analdehyde, can lead to production of undesirable strong aldehyde acids,e.g., n-C₃ H₇ CH(OH)P(O)(OH)₂.

Indeed even highly desirable sterically-hindered organobisphosphiteswhich are not very hydrolyzable can react with the aldehyde product toform poisoning organophosphites, e.g., organomonophosphites, which arenot only catalytic inhibitors, but far more susceptible to hydrolysisand the formation of such aldehyde acid byproducts, e.g., hydroxy alkylphosphonic acids, as shown, for example, in U.S. Pat. Nos. 5,288,918 and5,364,950. Further, the hydrolysis of organophosphite ligands may beconsidered as being autocatalytic in view of the production of suchphosphorus acidic compounds, e.g., H₃ PO₃, aldehyde acids such ashydroxy alkyl phosphonic acids, H₃ PO₄ and the like, and if leftunchecked the catalyst system of the continuous liquid recyclehydroformylation process will become more and more acidic in time. Thusin time the eventual build-up of an unacceptable amount of suchphosphorus acidic materials can cause the total destruction of theorganophosphite present, thereby rendering the hydroformylation catalysttotally ineffective (deactivated) and the valuable rhodium metalsusceptible to loss, e.g., due to precipitation and/or depositing on thewalls of the reactor. Accordingly, a successful method for preventingand/or lessening such hydrolytic degradation of the organophosphiteligand and deactivation of the catalyst would be highly desirable to theart.

DISCLOSURE OF THE INVENTION

It has now been discovered that free organopolyphosphite ligand at loworganopolyphosphite ligand to metal ratios may be employed toeffectively prevent and/or lessen hydrolytic degradation of theorganopolyphosphite ligand and deactivation of metal-organopolyphosphiteligand complex catalysts that may occur over the course of time duringprocesses which employ metal-organopolyphosphite ligand complexcatalysts. It has been surprisingly discovered that by reducing theamount of free organopolyphosphite ligand to preferred levels of fromzero to about 4 moles per mole of metal, adventitious hydrolysis can bereduced so that the processes can be operated below the threshold forautocatalytic hydrolysis of organopolyphosphite ligand and at aresidence time in the reactors sufficient to prevent and/or lessenhydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst.The processes of this invention can be operated at high raw materialefficiencies, e.g., high conversion of olefinic unsaturated compounds.

This invention relates in part to a process which comprises reacting oneor more reactants in the presence of a metal-organopolyphosphite ligandcomplex catalyst to produce a reaction product fluid comprising one ormore products, wherein said process is conducted at a freeorganopolyphosphite ligand concentration sufficient to prevent and/orlessen hydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst.

This invention also relates in part to a process which comprisesreacting one or more reactants in the presence of ametal-organopolyphosphite ligand complex catalyst to produce a reactionproduct fluid comprising one or more products, wherein said process isconducted (a) at a free organopolyphosphite ligand concentrationsufficient to prevent and/or lessen hydrolytic degradation of theorganopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst and (b) at a reactionzone and/or separator zone residence time sufficient to prevent and/orlessen hydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst.

This invention further relates in part to an improved process forproducing one or more products which comprises (i) reacting in at leastone reaction zone one or more reactants in the presence of ametal-organopolyphosphite ligand complex catalyst to produce a reactionproduct fluid comprising one or more products and (ii) separating in atleast one separation zone or in said at least one reaction zone the oneor more products from said reaction product fluid, the improvementcomprising preventing and/or lessening hydrolytic degradation of theorganopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst by conducting saidprocess (a) at a free organopolyphosphite ligand concentrationsufficient to prevent and/or lessen hydrolytic degradation of theorganopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst, and (b) at a reactionzone and/or separator zone residence time sufficient to prevent and/orlessen hydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst;and by treating in at least one acid removal zone at least a portion ofsaid reaction product fluid derived from said process and which alsocontains phosphorus acidic compounds formed during said process with anacid removal substance sufficient to remove at least some amount of thephosphorus acidic compounds from said reaction product fluid.

This invention yet further relates in part to an improved process forproducing one or more products which comprises (i) reacting in at leastone reaction zone one or more reactants in the presence of ametal-organopolyphosphite ligand complex catalyst to produce a reactionproduct fluid comprising one or more products and (ii) separating in atleast one separation zone or in said at least one reaction zone the oneor more products from said reaction product fluid, the improvementcomprising preventing and/or lessening hydrolytic degradation of theorganopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst by conducting saidprocess (a) at a free organopolyphosphite ligand concentrationsufficient to prevent and/or lessen hydrolytic degradation of theorganopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst, and (b) at a reactionzone and/or separator zone residence time sufficient to prevent and/orlessen hydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst;and by removing phosphorus acidic compounds from said reaction productfluid derived from said process by (a) withdrawing from said at leastone reaction zone or said at least one separation zone at least aportion of a reaction product fluid derived from said process and whichalso contains phosphorus acidic compounds formed during said process,(b) treating in at least one acid removal zone at least a portion of thewithdrawn reaction product fluid derived from said process and whichalso contains phosphorus acidic compounds formed during said processwith an acid removal substance sufficient to remove at least some amountof the phosphorus acidic compounds from said reaction product fluid, and(c) returning the treated reaction product fluid to said at least onereaction zone or said at least one separation zone.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphical representation of free ligand concentration(grams/liter) versus average ligand usage (grams/liter/day) based on theexperimental data set out in Table A herein.

DETAILED DESCRIPTION

General Processes

The processes of this invention may be asymmetric or non-asymmetric, thepreferred processes being non-asymmetric, and may be conducted in anycontinuous or semi-continuous fashion and may involve any catalystliquid and/or gas recycle operation desired. The particular processesfor producing products from one or more reactants, as well as thereaction conditions and ingredients of the processes are not criticalfeatures of this invention. The processing techniques of this inventionmay correspond to any of the known processing techniques heretoforeemployed in conventional processes. For instance, the processes can beconducted in either the liquid or gaseous states and in a continuous,semi-continuous or batch fashion and involve a liquid recycle and/or gasrecycle operation or a combination of such systems as desired. Likewise,the manner or order of addition of the reaction ingredients, catalystand solvent are also not critical and may be accomplished in anyconventional fashion. As used herein, the term "reaction product fluid"is contemplated to include, but not limited to, a reaction mixturecontaining an amount of any one or more of the following: (a) ametal-organopolyphosphite ligand complex catalyst, (b) freeorganopolyphosphite ligand, (c) one or more phosphorus acidic compoundsformed in the reaction, (d) aldehyde product formed in the reaction, (e)unreacted reactants, and (f) an organic solubilizing agent for saidmetal-organopolyphosphite ligand complex catalyst and said freeorganopolyphosphite ligand. The reaction product fluid encompasses, butis not limited to, (a) the reaction medium in the reaction zone, (b) thereaction medium stream on its way to the separation zone, (c) thereaction medium in the separation zone, (d) the recycle stream betweenthe separation zone and the reaction zone, (e) the reaction mediumwithdrawn from the reaction zone or separation zone for treatment in theacid removal zone, (f) the withdrawn reaction medium treated in the acidremoval zone, (g) the treated reaction medium returned to the reactionzone or separation zone, and (h) reaction medium in external cooler.

This invention encompasses the carrying out of known conventionalsyntheses in a conventional fashion employing ametal-organopolyphosphite ligand complex catalyst and freeorganopolyphosphite ligand at low organopolyphosphite ligand to metalratios to effectively prevent and/or lessen hydrolytic degradation ofthe organopolyphosphite ligand and deactivation ofmetal-organopolyphosphite ligand complex catalysts that may occur overthe course of time during processes which employmetal-organopolyphosphite ligand complex catalysts.

Illustrative processes include, for example, hydroformylation,hydroacylation (intramolecular and intermolecular), hydrocyanation,hydroamidation, hydroesterification, aminolysis, alcoholysis,carbonylation, olefin isomerization, transfer hydrogenation and thelike. Preferred processes involve the reaction of organic compounds withcarbon monoxide, or with carbon monoxide and a third reactant, e.g.,hydrogen, or with hydrogen cyanide, in the presence of a catalyticamount of a metal-organopolyphosphite ligand complex catalyst. The mostpreferred processes include hydroformylation, hydrocyanation andcarbonylation.

Hydroformylation can be carried out in accordance with conventionalprocedures known in the art. For example, aldehydes can be prepared byreacting an olefinic compound, carbon monoxide and hydrogen underhydroformylation conditions in the presence of ametal-organopolyphosphite ligand complex catalyst described herein.Alternatively, hydroxyaldehydes can be prepared by reacting an epoxide,carbon monoxide and hydrogen under hydroformylation conditions in thepresence of a metal-organopolyphosphite ligand complex catalystdescribed herein. The hydroxyaldehyde can be hydrogenated to a diol,e.g., hydroxypropionaldehyde can be hydrogenated to propanediol.Hydroformylation processes are described more fully hereinbelow.

Intramolecular hydroacylation can be carried out in accordance withconventional procedures known in the art. For example, aldehydescontaining an olefinic group 3 to 7 carbons removed can be converted tocyclic ketones under hydroacylation conditions in the presence of ametal-organopolyphosphite ligand complex catalyst described herein.

Intermolecular hydroacylation can be carried out in accordance withconventional procedures known in the art. For example, ketones can beprepared by reacting an olefin and an aldehyde under hydroacylationconditions in the presence of a metal-organopolyphosphite ligand complexcatalyst described herein.

Hydrocyanation can be carried out in accordance with conventionalprocedures known in the art. For example, nitrile compounds can beprepared by reacting an olefinic compound and hydrogen cyanide underhydrocyanation conditions in the presence of a metal-organopolyphosphiteligand complex catalyst described herein. A preferred hydrocyanationprocess involves reacting a nonconjugated acyclic aliphatic monoolefin,a monoolefin conjugated to an ester group, e.g., methyl pent-2-eneoate,or a monoolefin conjugated to a nitrile group, e.g., 3-pentenenitrile,with a source of hydrogen cyanide in the presence of a catalystprecursor composition comprising zero-valent nickel and a bidentatephosphite ligand to produce a terminal organonitrile, e.g.,adiponitrile, alkyl 5-cyanovalerate or 3-(perfluoroalkyl)propionitrile.Preferably, the reaction is carried out in the presence of a Lewis acidpromoter. Illustrative hydrocyanation processes are disclosed in U.S.Pat. No. 5,523,453 and WO 95/14659, the disclosures of which areincorporated herein by reference.

Hydroamidation can be carried out in accordance with conventionalprocedures known in the art. For example, amides can be prepared byreacting an olefin, carbon monoxide and a primary or secondary amine orammonia under hydroamidation conditions in the presence of ametal-organopolyphosphite ligand complex catalyst described herein.

Hydroesterification can be carried out in accordance with conventionalprocedures known in the art. For example, esters can be prepared byreacting an olefin, carbon monoxide and an alcohol underhydroesterification conditions in the presence of ametal-organopolyphosphite ligand complex catalyst described herein.

Aminolysis can be carried out in accordance with conventional proceduresknown in the art. For example, amines can be prepared by reacting anolefin with a primary or secondary amine under aminolysis conditions inthe presence of a metal-organopolyphosphite ligand complex catalystdescribed herein.

Alcoholysis can be carried out in accordance with conventionalprocedures known in the art. For example, ethers can be prepared byreacting an olefin with an alcohol under alcoholysis conditions in thepresence of a metal-organopolyphosphite ligand complex catalystdescribed herein.

Carbonylation can be carried out in accordance with conventionalprocedures known in the art. For example, lactones can be prepared bytreatment of allylic alcohols with carbon monoxide under carbonylationconditions in the presence of a metal-organopolyphosphite ligand complexcatalyst described herein.

Isomerization can be carried out in accordance with conventionalprocedures known in the art. For example, allylic alcohols can beisomerized under isomerization conditions to produce aldehydes in thepresence of a metal-organopolyphosphite ligand complex catalystdescribed herein.

Transfer hydrogenation can be carried out in accordance withconventional procedures known in the art. For example, alcohols can beprepared by reacting a ketone and an alcohol under transferhydrogenation conditions in the presence of a metal-organopolyphosphiteligand complex catalyst described herein.

The permissible starting material reactants encompassed by the processesof this invention are, of course, chosen depending on the particularprocess desired. Such starting materials are well known in the art andcan be used in conventional amounts in accordance with conventionalmethods. Illustrative starting material reactants include, for example,substituted and unsubstituted aldehydes (intramolecular hydroacylation),olefins (hydroformylation, carbonylation, intermolecular hydroacylation,hydrocyanation, hydroamidation, hydroesterification, aminolysis,alcoholysis), ketones (transfer hydrogenation), epoxides(hydroformylation, hydrocyanation), alcohols (carbonylation) and thelike. Illustrative of suitable reactants for effecting the processes ofthis invention are set out in Kirk-Othmer, Encyclopedia of ChemicalTechnology, Fourth Edition, 1996, the pertinent portions of which areincorporated herein by reference.

Illustrative metal-organopolyphosphite ligand complex catalystsemployable in the processes encompassed by this invention are known inthe art and include those disclosed in the below mentioned patents. Ingeneral such catalysts may be preformed or formed in situ as describedin such references and consist essentially of metal in complexcombination with an organopolyphosphite ligand or an organophosphorusligand as the case may be. The active species may also contain carbonmonoxide and/or hydrogen directly bonded to the metal.

The catalysts useful in the processes of this invention include ametal-organopolyphosphite ligand complex catalyst, which can beoptically active or non-optically active. The permissible metals whichmake up the metal-organopolyphosphite ligand complexes include Group 8,9 and 10 metals selected from rhodium (Rh), cobalt (Co), iridium (Ir),ruthenium (Ru), iron (Fe), nickel (Ni), palladium (Pd), platinum (Pt),osmium (Os) and mixtures thereof, with the preferred metals beingrhodium, cobalt, iridium and ruthenium, more preferably rhodium, cobaltand ruthenium, especially rhodium. Other permissible metals includeGroup 6 metals selected from chromium (Cr), molybdenum (Mo), tungsten(W) and mixtures thereof Mixtures of metals from Groups 6, 8, 9 and 10may also be used in this invention.

The permissible organopolyphosphite ligands which make up themetal-organopolyphosphite ligand complexes and free organopolyphosphiteligand include di-, tri- and higher polyorganophosphites. Mixtures ofsuch ligands may be employed if desired in the metal-organopolyphosphiteligand complex catalyst and/or any free organopolyphosphite ligand andsuch mixtures may be the same or different. This invention is notintended to be limited in any manner by the permissibleorganopolyphosphite ligands or mixtures thereof. It is to be noted thatthe successful practice of this invention does not depend and is notpredicated on the exact structure of the metal-organopolyphosphiteligand complex species, which may be present in their mononuclear,dinuclear and/or higher nuclearity forms. Indeed, the exact structure isnot known. Although it is not intended herein to be bound to any theoryor mechanistic discourse, it appears that the catalytic species may inits simplest form consist essentially of the metal in complexcombination with the organopolyphosphite ligand and carbon monoxideand/or hydrogen when used.

The term "complex" as used herein and in the claims means a coordinationcompound formed by the union of one or more electronically richmolecules or atoms capable of independent existence with one or moreelectronically poor molecules or atoms, each of which is also capable ofindependent existence. For example, the organopolyphosphite ligandsemployable herein may possess one or more phosphorus donor atoms, eachhaving one available or unshared pair of electrons which are eachcapable of forming a coordinate covalent bond independently or possiblyin concert (e.g., via chelation) with the metal. Carbon monoxide (whichis also properly classified as a ligand) can also be present andcomplexed with the metal. The ultimate composition of the complexcatalyst may also contain an additional ligand, e.g., hydrogen or ananion satisfying the coordination sites or nuclear charge of the metal.Illustrative additional ligands include, for example, halogen (Cl, Br,I), alkyl, aryl, substituted aryl, acyl, CF₃, C₂ F₅, CN, (R)₂ PO andRP(O)(OH)O (wherein each R is the same or different and is a substitutedor unsubstituted hydrocarbon radical, e.g., the alkyl or aryl), acetate,acetylacetonate, SO₄, PF₄, PF₆, NO₂, NO₃, CH₃ O, CH₂ ═CHCH₂, CH₃CH═CHCH₂, C₆ H₅ CN, CH₃ CN, NH₃, pyridine, (C₂ H₅)₃ N, mono-olefins,diolefins and triolefins, tetrahydrofuran, and the like. It is of courseto be understood that the complex species are preferably free of anyadditional organic ligand or anion that might poison the catalyst orhave an undue adverse effect on catalyst performance. It is preferred inthe metal-organopolyphosphite ligand complex catalyzed reactions thatthe active catalysts be free of halogen and sulfur directly bonded tothe metal, although such may not be absolutely necessary.

The number of available coordination sites on such metals is well knownin the art. Thus the catalytic species may comprise a complex catalystmixture, in their monomeric, dimeric or higher nuclearity forms, whichare preferably characterized by at least oneorganopolyphosphite-containing molecule complexed per one molecule ofmetal, e.g., rhodium. For instance, it is considered that the catalyticspecies of the preferred catalyst employed in a hydroformylationreaction may be complexed with carbon monoxide and hydrogen in additionto the organopolyphosphite ligands in view of the carbon monoxide andhydrogen gas employed by the hydroformylation reaction.

The organopolyphosphites that may serve as the ligand of themetal-organopolyphosphite ligand complex catalyst and/or free ligand ofthe processes and reaction product fluids of this invention may be ofthe achiral (optically inactive) or chiral (optically active) type andare well known in the art. Achiral organopolyphosphites are preferred.

Among the organopolyphosphites that may serve as the ligand of themetal-organopolyphosphite ligand complex catalyst containing reactionproduct fluids of this invention and/or any free organopolyphosphiteligand of the process that might also be present in said reactionproduct fluids are organopolyphosphite compounds described below. Suchorganopolyphosphite ligands employable in this invention and/or methodsfor their preparation are well known in the art.

Representative organopolyphosphites contain two or more tertiary(trivalent) phosphorus atoms and may include those having the formula:##STR1## wherein X represents a substituted or unsubstituted n-valentorganic bridging radical containing from 2 to 40 carbon atoms, each R¹is the same or different and represents a divalent organic radicalcontaining from 4 to 40 carbon atoms, each R² is the same or differentand represents a substituted or unsubstituted monovalent hydrocarbonradical containing from 1 to 24 carbon atoms, a and b can be the same ordifferent and each have a value of 0 to 6, with the proviso that the sumof a+b is 2 to 6 and n equals a+b. Of course it is to be understood thatwhen a has a value of 2 or more, each R¹ radical may be the same ordifferent, and when b has a value of 1 or more, each R² radical may bethe same or different.

Representative n-valent (preferably divalent) hydrocarbon bridgingradicals represented by X and representative divalent organic radicalsrepresented by R¹ above, include both acyclic radicals and aromaticradicals, such as alkylene, alkylene-Q_(m) -alkylene, cycloalkylene,arylene, bisarylene, arylene-alkylene, and arylene-(CH₂)_(y) --Q_(m)--(CH₂)_(y) -arylene radicals, and the like, wherein each y is the sameor different and is a value of 0 or 1, Q represents a divalent bridginggroup selected from --C(R³)₂ --, --O--, --S--, --NR⁴ --, Si(R⁵)₂ --and--CO--, wherein each R³ is the same or different and representshydrogen, an alkyl radical having from 1 to 12 carbon atoms, phenyl,tolyl, and anisyl, R⁴ represents hydrogen or a substituted orunsubstituted monovalent hydrocarbon radical, e.g., an alkyl radicalhaving 1 to 4 carbon atoms; each R⁵ is the same or different andrepresents hydrogen or an alkyl radical, and m is a value of 0 or 1. Themore preferred acyclic radicals represented by X and R¹ above aredivalent alkylene radicals, while the more preferred aromatic radicalsrepresented by X and R¹ above are divalent arylene and bisaryleneradicals, such as disclosed more fully, for example, in U.S. Pat. Nos.4,769,498; 4,774,361: 4,885,401; 5,179,055; 5,113,022; 5,202,297;5,235,113; 5,264,616 and 5,364,950, and European Patent ApplicationPublication No. 662,468, and the like, the disclosures of which areincorporated herein by reference. Representative preferred monovalenthydrocarbon radicals represented by each R² radical above include alkyland aromatic radicals.

Illustrative preferred organopolyphosphites may include bisphosphitessuch as those of Formulas (II) to (IV) below: ##STR2## wherein each R¹,R² and X of Formulas (II) to (IV) are the same as defined above forFormula (I). Preferably each R¹ and X represents a divalent hydrocarbonradical selected from alkylene, arylene, arylene-alkylene-arylene, andbisarylene, while each R² radical represents a monovalent hydrocarbonradical selected from alkyl and aryl radicals. Organopolyphosphiteligands of such Formulas (II) to (IV) may be found disclosed, forexample, in U.S. Pat. Nos. 4,668,651; 4,748,261; 4,769,498; 4,774,361;4,885,401; 5,113,022; 5,179,055; 5,202,297; 5,235,113; 5,254,741;5,264,616; 5,312,996; 5,364,950; and 5,391,801; the disclosures of allof which are incorporated herein by reference.

Representative of more preferred classes of organobisphosphites arethose of the following Formulas (V) to (VII): ##STR3## wherein Q R¹, R²,X, m, and y are as defined above, and each Ar is the same or differentand represents a substituted or unsubstituted aryl radical. Mostpreferably X represents a divalent aryl-(CH₂)_(y) --(Q)_(m) --(CH₂)_(y)-aryl radical wherein each y individually has a value of 0 or 1; m has avalue of 0 or 1 and Q is --O--, --S--or --C(R³)₂ where each R³ is thesame or different and represents hydrogen or a methyl radical. Morepreferably each alkyl radical of the above defined R² groups may containfrom 1 to 24 carbon atoms and each aryl radical of the above-defined Ar,X, R¹ and R² groups of the above Formulas (V) to (VII) may contain from6 to 18 carbon atoms and said radicals may be the same or different,while the preferred alkylene radicals of X may contain from 2 to 18carbon atoms and the preferred alkylene radicals of R¹ may contain from5 to 18 carbon atoms. In addition, preferably the divalent Ar radicalsand divalent aryl radicals of X of the above formulas are phenyleneradicals in which the bridging group represented by --(CH₂)_(y)--(Q)_(m) --CH₂)_(y) -- is bonded to said phenylene radicals inpositions that are ortho to the oxygen atoms of the formulas thatconnect the phenylene radicals to their phosphorus atom of the formulae.It is also preferred that any substituent radical when present on suchphenylene radicals be bonded in the para and/or ortho position of thephenylene radicals in relation to the oxygen atom that bonds the givensubstituted phenylene radical to its phosphorus atom.

Moreover, if desired any given organopolyphosphite in the above Formulas(I) to (VII) may be an ionic phosphite, i.e., may contain one or moreionic moieties selected from the group consisting of:

SO₃ M wherein M represents inorganic or organic cation,

PO₃ M wherein M represents inorganic or organic cation,

N(R⁶)₃ X¹ wherein each R⁶ is the same or different and represents ahydrocarbon radical containing from 1 to 30 carbon atoms, e.g., alkyl,aryl, alkaryl, aralkyl, and cycloalkyl radicals, and X¹ representsinorganic or organic anion,

CO₂ M wherein M represents inorganic or organic cation,

as described, for example, in U.S. Pat. Nos. 5,059,710; 5,113,0225,114,473; 5,449,653; and European Patent Application Publication No.435,084, the disclosures of which are incorporated herein by reference.Thus, if desired, such organopolyphosphite ligands may contain from 1 to3 such ionic moieties, while it is preferred that only one such ionicmoiety be substituted on any given aryl moiety in theorganopolyphosphite ligand when the ligand contains more than one suchionic moiety. As suitable counter-ions, M and X¹, for the anionicmoieties of the ionic organopolyphosphites there can be mentionedhydrogen (i.e. a proton), the cations of the alkali and alkaline earthmetals, e.g., lithium, sodium, potassium, cesium, rubidium, calcium,barium, magnesium and strontium, the ammonium cation and quaternaryammonium cations, phosphonium cations, arsonium cations and iminiumcations. Suitable anionic atoms of radicals include, for example,sulfate, carbonate, phosphate, chloride, acetate, oxalate and the like.

Of course any of the R¹, R², X, Q and Ar radicals of such non-ionic andionic organopolyphosphites of Formulas (I) to (VII) above may besubstituted if desired, with any suitable substituent containing from 1to 30 carbon atoms that does not unduly adversely affect the desiredresult of the process of this invention. Substituents that may be onsaid radicals in addition of course to corresponding hydrocarbonradicals such as alkyl, aryl, aralkyl, alkaryl and cyclohexylsubstituents, may include for example silyl radicals such as --Si(R⁷)₃ ;amino radicals such as --N(R⁷)₂ ; phosphine radicals such as-aryl-P(R⁷)₂ ; acyl radicals such as --C(O)R⁷ acyloxy radicals such as--OC(O)R⁷ ; amido radicals such as --CON(R⁷)₂ and --N(R⁷)COR⁷ ; sulfonylradicals such as --SO₂ R⁷, alkoxy radicals such as --OR⁷ ; sulfinylradicals such as --SOR⁷, sulfenyl radicals such as --SR⁷, phosphonylradicals such as --P(O)(R⁷)₂, as well as halogen, nitro, cyano,trifluoromethyl, hydroxy radicals, and the like, wherein each R⁷ radicalindividually represents the same or different monovalent hydrocarbonradical having from 1 to 18 carbon atoms (e.g., alkyl, aryl, aralkyl,alkaryl and cyclohexyl radicals), with the proviso that in aminosubstituents such as --N(R⁷)₂ each R⁷ taken together can also representa divalent bridging group that forms a heterocyclic radical with thenitrogen atom, and in amido substituents such as --C(O)N(R⁷)₂ and--N(R⁷)COR⁷ each R⁷ bonded to N can also be hydrogen. Of course it is tobe understood that any of the substituted or unsubstituted hydrocarbonradicals groups that make up a particular given organopolyphosphite maybe the same or different.

More specifically illustrative substituents include primary, secondaryand tertiary alkyl radicals such as methyl, ethyl, n-propyl, isopropyl,butyl, sec-butyl, t-butyl, neo-pentyl, n-hexyl, amyl, sec-amyl, t-amyl,iso-octyl, decyl, octadecyl, and the like; aryl radicals such as phenyl,naphthyl and the like; aralkyl radicals such as benzyl, phenylethyl,triphenylmethyl, and the like; alkaryl radicals such as tolyl, xylyl,and the like; alicyclic radicals such as cyclopentyl, cyclohexyl,1-methylcyclohexyl, cyclooctyl, cyclohexylethyl, and the like; alkoxyradicals such as methoxy, ethoxy, propoxy, t-butoxy, --OCH₂ CH₂ OCH₃,--O(CH₂ CH₂)₂ OCH₃, --O(CH₂ CH₂)₃ OCH₃, and the like; aryloxy radicalssuch as phenoxy and the like; as well as silyl radicals such as--Si(CH₃)₃, --Si(OCH₃)₃, --Si(C₃ H₇)₃, and the like; amino radicals suchas --NH₂, --N(CH₃)₂, --NHCH₃, --NH(C₂ H₅), and the like; arylphosphineradicals such as --P(C₆ H₅)₂, and the like; acyl radicals such as--C(O)CH₃, --C(O)C₂ H₅, --C(O)C₆ H₅, and the like; carbonyloxy radicalssuch as --C(O)OCH₃ and the like; oxycarbonyl radicals such as --O(CO)C₆H₅, and the like; amido radicals such as --CONH₂, --CON(CH₃)₂,--NHC(O)CH₃, and the like; sulfonyl radicals such as --S(O)₂ C₂ H₅ andthe like; sulfinyl radicals such as --S(O)CH₃ and the like; sulfenylradicals such as --SCH₃, --SC₂ H₅, --SC₆ H₅, and the like; phosphonylradicals such as --P(O)(C₆ H₅)₂, --P(O)(CH₃)₂, --P(O)(C₂ H₅)₂, --P(O)(C₃H₇)₂, --P(O)(C₄ H₉)₂, --P(O)(C₆ H₁₃)₂ --P(O)CH₃ (C₆ H₅), --P(O)(H)(C₆H5), and the like.

Specific illustrative examples of such organobisphosphite ligandsinclude the following;

6,6'- 4,4'-bis(1,1-dimethylethyl)-1,1'-binaphthyl!-2,2'-diyl!bis(oxy)!bis-dibenzo d,f!1,3,2!-dioxaphosphepin having the formula: ##STR4## 6,6'-3,3'-bis(1,1-dimethylethy)-5,5'-dimethoxy-1,1'-biphenyl!-2,2'-diyl!bis(oxy)!bis-dibenzo d,f! 1,3,2!dioxaphosphepinhaving the formula: ##STR5## 6,6'-3,3',5,5'-tetrakis(1,1-dimethylpropyl)-1,1'-biphenyl!-2,2'-diyl!bis(oxy)!bis-dibenzo d,f! 1,3,2!dioxaphosphepinhaving the formula: ##STR6## 6,6'-3,3',5,5'-tetrakis(1,1-dimethylethyl)-1,1'-biphenyl!-2,2'-diyl!bis(oxy)!bis-dibenzod,f! 1,3,2!-dioxaphosphepin having the formula: ##STR7## (2R,4R)-di2,2'-(3,3',5,5'-tetrakis-tert-amyl-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR8## (2R,4R)-di2,2'-(3,3',5,5'-tetrakis-tert-butyl-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR9## (2R,4R)-di2,2'-(3,3'-di-amyl-5,5'-dimethoxy-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR10## (2R,4R)-di2,2'-(3,3'-di-tert-butyl-5,5'-dimethyl-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR11## (2R,4R)-di2,2'-(3,3'-di-tert-butyl-5,5'-diethoxy-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR12## (2R,4R)-di2,2'-(3,3'-di-tert-butyl-5,5'-diethyl-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR13## (2R,4R)-di2,2'-(3,3'-di-tert-butyl-5,5'-dimethoxy-1,1'-biphenyl)!-2,4-pentyldiphosphitehaving the formula: ##STR14## 6- 2'-(4,6-bis(1,1-dimethylethyl)-1,3,2-benzodioxaphosphol-2-yl)oxy!-3,3'-bis(1,1-dimethylethyl)-5,5'-dimethoxy1,1'-biphenyl!-2-yl!oxy!-4,8-bis(1,1-dimethylethyl)-2,10-dimethoxydibenzod,f! 1,3,2!dioxaphosphepin having the formula: ##STR15## 6- 2'-1,3,2-benzodioxaphosphol-2-yl)oxy!-3,3'-bis(1,1-dimethylethyl)-5,5'-dimethoxy1,1'-biphenyl!-2-yl!oxy!-4,8-bis(1,1-dimethylethyl)-2,10-dimethoxydibenzod,f! 1,3,2!dioxaphosphepin having the formula: ##STR16## 6- 2'-(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)oxy!-3,3'-bis(1,1-dimethylethyl)-5,5'-dimethoxy1,1'-biphenyl!-2-yl!oxy!-4,8-bis(1,1-dimethylethyl)-2,10-dimethoxydibenzod,f! 1,3,2!dioxaphosphepin having the formula: ##STR17## 2'-4,8-bis(1,1-dimethylethyl)-2,10-dimethoxydibenzo d,f!1,3,2!-dioxaphosphepin-6-yl!oxy!-3,3'-bis(1,1-dimethylethyl)-5,5'-dimethoxy1,1'-biphenyl!-2-yl bis(4-hexylphenyl)ester of phosphorous acid havingthe formula: ##STR18## 2- 4,8,-bis(1,1-dimethylethyl),2,10-dimethoxydibenzo- d,f!1,3,2!dioxophosphepin-6-yl!oxy!-3-(1,1-dimethylethyl)-5-methoxyphenyl!methyl!-4-methoxy,6-(1,1-dimethylethyl)phenyl diphenyl ester of phosphorous acid havingthe formula: ##STR19## 3-methoxy-1,3-cyclohexamethylene tetrakis3,6-bis(1,1-dimethylethyl)-2-naphthalenyl!ester of phosphorous acidhaving the formula: ##STR20## 2,5-bis(1,1-dimethylethyl)-1,4-phenylenetetrakis 2,4-bis(1,1-dimethylethyl)phenyl!ester of phosphorous acidhaving the formula: ##STR21## methylenedi-2,1-phenylene tetrakis2,4-bis(1,1-dimethylethyl)phenyl!ester of phosphorous acid having theformula: ##STR22## 1,1'-biphenyl!-2,2'-diyl tetrakis2-(1,1-dimethylethyl)-4-methoxyphenyl!ester of phosphorous acid havingthe formula: ##STR23##

As noted above, the metal-organopolyphosphite ligand complex catalystsemployable in this invention may be formed by methods known in the art.The metal-organopolyphosphite ligand complex catalysts may be inhomogeneous or heterogeneous form. For instance, preformed rhodiumhydrido-carbonyl-organopolyphosphite ligand catalysts may be preparedand introduced into the reaction mixture of a particular process. Morepreferably, the metal-organopolyphosphite ligand complex catalysts canbe derived from a rhodium catalyst precursor which may be introducedinto the reaction medium for in situ formation of the active catalyst.For example, rhodium catalyst precursors such as rhodium dicarbonylacetylacetonate, Rh₂ O₃, Rh₄ (CO)₁₂, Rh₆ (CO)₁₆, Rh(NO₃)₃ and the likemay be introduced into the reaction mixture along with theorganopolyphosphite ligand for the in situ formation of the activecatalyst. In a preferred embodiment of this invention, rhodiumdicarbonyl acetylacetonate is employed as a rhodium precursor andreacted in the presence of a solvent with the organopolyphosphite ligandto form a catalytic rhodium-organopolyphosphite ligand complex precursorwhich is introduced into the reaction zone along with excess (free)organopolyphosphite ligand for the in situ formation of the activecatalyst. In any event, it is sufficient for the purpose of thisinvention that carbon monoxide, hydrogen and organopolyphosphitecompound are all ligands that are capable of being complexed with themetal and that an active metal-organopolyphosphite ligand catalyst ispresent in the reaction mixture under the conditions used in thehydroformylation reaction.

More particularly, a catalyst precursor composition can be formedconsisting essentially of a solubilized metal-organopolyphosphite ligandcomplex precursor catalyst, an organic solvent and freeorganopolyphosphite ligand. Such precursor compositions may be preparedby forming a solution of a rhodium starting material, such as a rhodiumoxide, hydride, carbonyl or salt, e.g., a nitrate, which may or may notbe in complex combination with a organopolyphosphite ligand as definedherein. Any suitable rhodium starting material may be employed, e.g.rhodium dicarbonyl acetylacetonate, Rh₂ O₃, Rh₄ (CO)₁₂, Rh₆ (CO)₁₆,Rh(NO₃)₃, and organopolyphosphite ligand rhodium carbonyl hydrides.Carbonyl and organopolyphosphite ligands, if not already complexed withthe initial rhodium, may be complexed to the rhodium either prior to orin situ during the process.

By way of illustration, the preferred catalyst precursor composition ofthis invention consists essentially of a solubilized rhodium carbonylorganopolyphosphite ligand complex precursor catalyst, a solvent andoptionally free organopolyphosphite ligand prepared by forming asolution of rhodium dicarbonyl acetylacetonate, an organic solvent and aorganopolyphosphite ligand as defined herein. The organopolyphosphiteligand readily replaces one of the carbonyl ligands of the rhodiumacetylacetonate complex precursor at room temperature as witnessed bythe evolution of carbon monoxide gas. This substitution reaction may befacilitated by heating the solution if desired. Any suitable organicsolvent in which both the rhodium dicarbonyl acetylacetonate complexprecursor and rhodium organopolyphosphite ligand complex precursor aresoluble can be employed. The amounts of rhodium complex catalystprecursor, organic solvent and organopolyphosphite ligand, as well astheir preferred embodiments present in such catalyst precursorcompositions may obviously correspond to those amounts employable in theprocesses of this invention. Experience has shown that theacetylacetonate ligand of the precursor catalyst is replaced after theprocess, e.g., hydroformylation, has begun with a different ligand,e.g., hydrogen, carbon monoxide or organopolyphosphite ligand, to formthe active complex catalyst as explained above. The acetylacetone whichis freed from the precursor catalyst under hydroformylation conditionsis removed from the reaction medium with the product aldehyde and thusis in no way detrimental to the hydroformylation process. The use ofsuch preferred rhodium complex catalytic precursor compositions providesa simple economical and efficient method for handling the rhodiumprecursor rhodium and hydroformylation start-up.

Accordingly, the metal-organopolyphosphite ligand complex catalysts usedin the processes of this invention consists essentially of the metalcomplexed with carbon monoxide, i.e., hydroformylation, and anorganopolyphosphite ligand, said ligand being bonded (complexed) to themetal in a chelated and/or non-chelated fashion. Moreover, theterminology "consists essentially of", as used herein, does not exclude,but rather includes, hydrogen complexed with the metal, in addition tocarbon monoxide and the organopolyphosphite ligand. Further, suchterminology does not exclude the possibility of other organic ligandsand/or anions that might also be complexed with the metal. Materials inamounts which unduly adversely poison or unduly deactivate the catalystare not desirable and so the catalyst most desirably is free ofcontaminants such as metal-bound halogen (e.g., chlorine, and the like)although such may not be absolutely necessary. The hydrogen and/orcarbonyl ligands of an active metal-organopolyphosphite ligand complexcatalyst may be present as a result of being ligands bound to aprecursor catalyst and/or as a result of in situ formation, e.g., due tothe hydrogen and carbon monoxide gases employed in hydroformylationprocess of this invention.

As noted above, the organopolyphosphite ligands can be employed as boththe ligand of the metal-organopolyphosphite ligand complex catalyst, aswell as, the free organopolyphosphite ligand that can be present in thereaction medium of the processes of this invention. In addition, it isto be understood that while the organopolyphosphite ligand of themetal-organopolyphosphite ligand complex catalyst and any excess freeorganopolyphosphite ligand preferably present in a given process of thisinvention are normally the same type of ligand, different types oforganopolyphosphite ligands, as well as, mixtures of two or moredifferent organopolyphosphite ligands may be employed for each purposein any given process, if desired.

The amount of metal-organopolyphosphite ligand complex catalyst presentin the reaction medium of a given process of this invention need only bethat minimum amount necessary to provide the given metal concentrationdesired to be employed and which will furnish the basis for at leastthat catalytic amount of metal necessary to catalyze the particularprocess desired. In general, metal concentrations in the range of fromabout 1 part per million to about 10,000 parts per million, calculatedas free metal, and ligand to metal mole ratios in the catalyst solutionranging from about 1:1 or less to about 200:1 or greater, should besufficient for most processes.

As noted above, in addition to the metal-organopolyphosphite ligandcomplex catalysts, the processes of this invention and especially thehydroformylation process can be carried out in the presence of freeorganopolyphosphite ligand. While the processes of this invention may becarried out in any excess amount of free organopolyphosphite liganddesired, the employment of free organopolyphosphite ligand may not beabsolutely necessary. Accordingly, in general, amounts of ligand of fromabout 1.1 or less to about 100, or higher if desired, moles per mole ofmetal (e.g., rhodium) present in the reaction medium should be suitablefor most purposes, particularly with regard to rhodium catalyzedhydroformylation; said amounts of ligand employed being the sum of boththe amount of ligand that is bound (complexed) to the metal present andthe amount of free (non-complexed) ligand present. Of course, ifdesired, make-up ligand can be supplied to the reaction medium of theprocess, at any time and in any suitable manner, to maintain apredetermined level of free ligand in the reaction medium.

As indicated above, the catalysts may be in heterogeneous form duringthe reaction and/or during the product separation. Such catalysts areparticularly advantageous in the hydroformylation of olefins to producehigh boiling or thermally sensitive aldehydes, so that the catalyst maybe separated from the products by filtration or decantation at lowtemperatures. For example, the rhodium catalyst may be attached to asupport so that the catalyst retains its solid form during both thehydroformylation and separation stages, or is soluble in a liquidreaction medium at high temperatures and then is precipitated oncooling.

As an illustration, the rhodium catalyst may be impregnated onto anysolid support, such as inorganic oxides, (i.e. alumina, silica, titania,or zirconia) carbon, or ion exchange resins. The catalyst may besupported on, or intercalated inside the pores of, a zeolite, glass orclay; the catalyst may also be dissolved in a liquid film coating thepores of said zeolite or glass. Such zeolite-supported catalysts areparticularly advantageous for producing one or more regioisomericaldehydes in high selectivity, as determined by the pore size of thezeolite. The techniques for supporting catalysts on solids, such asincipient wetness, which will be known to those skilled in the art. Thesolid catalyst thus formed may still be complexed with one or more ofthe ligands defined above. Descriptions of such solid catalysts may befound in for example: J. Mol. Cat. 1991, 70, 363-368; Catal. Lett. 1991,8, 209-214; J. Organomet. Chem, 1991, 403, 221-227; Nature, 1989, 339,454-455; J. Catal. 1985, 96, 563-573; J. Mol. Cat. 1987, 39, 243-259.

The metal, e.g., rhodium, catalyst may be attached to a thin film ormembrane support, such as cellulose acetate or polyphenylenesulfone, asdescribed in for example J. Mol. Cat. 1990, 63, 213-221.

The metal, e.g., rhodium, catalyst may be attached to an insolublepolymeric support through an organophosphorus-containing ligand, such asa phosphite, incorporated into the polymer. The supported catalyst isnot limited by the choice of polymer or phosphorus-containing speciesincorporated into it. Descriptions of polymer-supported catalysts may befound in for example: J. Mol. Cat. 1993, 83, 17-35; Chemtech 1983, 46;J. Am. Chem. Soc. 1987, 109, 7122-7127.

In the heterogeneous catalysts described above, the catalyst may remainin its heterogeneous form during the entire process and catalystseparation process. In another embodiment of the invention, the catalystmay be supported on a polymer which, by the nature of its molecularweight, is soluble in the reaction medium at elevated temperatures, butprecipitates upon cooling, thus facilitating catalyst separation fromthe reaction mixture. Such "soluble" polymer-supported catalysts aredescribed in for example: Polymer, 1992, 33, 161; J. Org. Chem. 1989,54, 2726-2730.

More preferably, the hydroformylation reaction is carried out in theslurry phase due to the high boiling points of the products, and toavoid decomposition of the aldehyde products. The catalyst may then beseparated from the product mixture, for example, by filtration ordecantation. The reaction product fluid may contain a heterogeneousmetal-organopolyphosphite ligand complex catalyst, e.g., slurry, or atleast a portion of the reaction product fluid may contact a fixedheterogeneous metal-organopolyphosphite ligand complex catalyst duringthe particular process. In an embodiment of this invention, themetal-organopolyphosphite ligand complex catalyst may be slurried in thereaction product fluid.

This invention involves reducing the degradation or consumption oforganopolyphosphite ligand, including adventitious hydrolysis, byreducing the concentration of free organopolyphosphite ligand present inthe reaction product fluid below conventional levels. In a homogeneousprocess, e.g., hydroformylation, the organopolyphosphite ligand normallyprovides three functions. First, it coordinates with the metal, e.g.,rhodium, and thereby influences the rate of hydroformylation. Secondly,through a combination of steric and electronic effects, it influencesthe ratio of linear to branched aldehyde. Finally, it stabilizes themetal, e.g., rhodium, against agglomeration to metal, e.g., rhodiummetal. The latter function is particularly important when the reactionproduct fluid is sent to a vaporizer for separation of aldehyde product.

In conventional triphenylphosphine-modified metal system, it is notuncommon to have 100 to 200 moles of triphenylphosphine per mole ofmetal in order to achieve both a high linear to branched aldehyde ratioand to minimize catalyst deactivation reactions.Organopolyphosphite-modified metal catalysts can also be operated atrelatively high ligand to metal ratios, e.g., from about 50 to about 100moles of the organopolyphosphite ligand per mole of metal.

A disadvantage of the high organopolyphosphite ligand to metal, e.g.,rhodium, ratios is the higher free organopolyphosphite ligandconcentrations in solution. At a specified level of acidity and aspecified water level, a consequence of the higher organopolyphosphiteligand concentration is a higher rate of hydrolysis of the desiredorganopolyphosphite ligand. This follows logically from the knowledgethat hydrolysis is primarily a function of temperature, reaction productfluid acidity, water concentration and organopolyphosphite ligandconcentration.

A difficult problem arises from the autocatalytic nature of thehydrolysis and the reaction zone residence time characteristics of, forexample, a continuous stirred tank reactor (CSTR). The reaction productfluid has an specified average residence time in the reaction zone. Thereaction product fluid is then removed from the reaction zone and/or theseparation zone where a treatment to remove acidity, e.g., aqueousbuffer treatment as described herein, and product removal can occur. Athigh organopolyphosphite ligand to rhodium ratios, the residence timeneeded to control reaction product fluid acidity below a thresholdlevel, above which autocatalysis is severe, is shorter than theresidence time required for olefin conversion and product removal.Operating the system at the residence time dictated by the increase inacidity could result in less than optimal raw material efficiencies.Operating the system at the residence time dictated by product removalcan significantly increase the hydrolysis of the desiredorganopolyphosphite ligand.

In accordance with this invention, it has been discovered thatorganopolyphosphite ligands can be employed at very loworganopolyphosphite ligand to metal ratios, e.g., as low as zero freemoles of organopolyphosphite ligand per mole of metal, and achieve allthree desirable benefits--rate, high linear to branched ratio and metalstabilization. By reducing the amount of free organopolyphosphite ligandto preferred levels of from zero to about 4 moles per mole of metal,adventitious hydrolysis can be reduced so that the process can beoperated below the threshold for autocatalytic hydrolysis oforganopolyphosphite ligand and can have a residence time in the reactionzone and/or separation zone sufficient to achieve high raw materialefficiencies, e.g., high conversion of olefinic unsaturated compounds.

In a preferred embodiment, the hydroformylation processes of thisinvention are operated on a continuous basis at a freeorganopolyphosphite ligand concentration such that hydrolyticdegradation of the organopolyphosphite ligand is less than about 1 gram,more preferably less than about 0.5 grams, and most preferably less thanabout 0.1 grams, of organopolyphosphite ligand per liter of reactionproduct fluid per day. The free organopolyphosphite ligand concentrationis preferably from 0 to about 16 grams, more preferably from 0 to about8 grams, and most preferably from 0 to about 1 gram, per liter ofreaction product fluid.

As indicated above, the processes of this invention preferably operateat high raw material efficiencies, e.g., high conversion of olefinicunsaturated compounds. The raw material efficiency will be dependent onthe reaction zone and/or separation zone residence time and, asindicated herein, the residence time will be dependent on controllingreaction product fluid acidity below a threshold level, above whichautocatalysis is severe, and achieving desired olefin conversion andproduct removal. The processes of this invention may be operated atessentially complete raw material conversions. Gas and/or liquid recycleprocesses as described herein may be employed in order to achieve thedesired high raw material efficiencies.

The permissible reaction conditions employable in the processes of thisinvention are, of course, chosen depending on the particular synthesesdesired. Such process conditions are well known in the art. All of theprocesses of this invention can be carried out in accordance withconventional procedures known in the art. Illustrative reactionconditions for conducting the processes of this invention are described,for example, in Kirk-Othmer, Encyclopedia of Chemical Technology, FourthEdition, 1996, the pertinent portions of which are incorporated hereinby reference. Depending on the particular process, operatingtemperatures may range from about --80° C. or less to about 500° C. orgreater and operating pressures can range from about 1 psig or less toabout 10,000 psig or greater.

The water concentration useful in this invention is not narrowlycritical and can vary over a wide range. The hydroformylation processesmay preferably be carried out in the presence of a minor amount ofwater, e.g., an amount ranging from about 0.05 to about 10 weightpercent or higher if desired, based on the total weight of the reactionproduct fluid, and about preferably from about 0.05 to about 5 weightpercent. Suitable water concentrations useful in this invention aredisclosed in U.S. Pat. No. 5,288,918, the disclosure of which isincorporated herein by reference. The amount of water employed by thesubject invention is sufficient to at least maintain the concentrationof phosphorus acidic compounds below the threshold level that causesrapid degradation of the organopolyphosphite ligand. Preferably, thehydroformylation process is operated below the threshold forautocatalytic hydrolysis of organopolyphosphite ligand.

For instance, a preferred quantity of water is the quantity whichensures that any degradation of the organopolyphosphite ligand proceedsby the "non-catalytic mechanism" as described in "The Kinetic Rate Lawfor Autocatalytic Reactions" by Mata-Perez et al., Journal of ChemicalEducation, Vol. 64, No. 11, November 1987, pages 925 to 927, rather thanby the "catalytic mechanism" described in said article. Typicallymaximum water concentrations are only governed by practicalconsiderations.

It is to be understood that the preferred hydroformylation process ofthis invention is still considered to be essentially a "non-aqueous"process, which is to say, any water present in the hydroformylationreaction medium is not present in an amount sufficient to cause eitherthe hydroformylation reaction or said medium to be considered asencompassing a separate aqueous or water phase or layer in addition toan organic phase.

The phosphorus acidic compound concentration in the hydroformylationprocesses of this invention is not narrowly critical and can vary over awide range. The hydroformylation processes may preferably be carried outin the presence of a minor amount of one or more phosphorus acidiccompounds, e.g., an amount ranging from about 1 part per million or lessto about 1000 parts per million or greater if desired, and morepreferably from about 1 part per million to about 200 parts per million,based on H₃ PO₄. The concentration of phosphorus acidic compounds in thehydroformylation processes of this invention is preferably below thethreshold level that causes rapid degradation of the organopolyphosphiteligand, i.e., below the threshold for autocatalytic hydrolysis of theorganopolyphosphite ligand. The concentration of phosphorus acidiccompounds in the hydroformylation processes of this invention is suchthat the pH of said reaction product fluid is from about 4 to about 9.The phosphorus acidic compound concentration is preferably controlled byemploying an aqueous buffer solution as described herein.

The hydroformylation processes of this invention are conducted for aperiod of time sufficient to produce the desired products. The exactreaction zone residence time employed is dependent, in part, uponfactors such as temperature, nature and proportion of startingmaterials, and the like. The reaction zone residence time will normallybe within the range of from about one-half to about 200 hours or more,and preferably from less than about one to about 10 hours. The reactionzone residence time should be such that the hydroformylation process canbe operated below the threshold for autocatalytic hydrolysis oforganopolyphosphite ligand and have a residence time in the reactionzone sufficient to achieve high raw material efficiencies, e.g., highconversion of olefinic unsaturated compounds.

The processes of this invention and preferably the hydroformylationprocess may be conducted in the presence of an organic solvent for themetal-organopolyphosphite ligand complex catalyst. The solvent may alsocontain dissolved water up to the saturation limit. Depending on theparticular catalyst and reactants employed, suitable organic solventsinclude, for example, alcohols, alkanes, alkenes, alkynes, ethers,aldehydes, ketones, esters, amides, amines, aromatics and the like. Anysuitable solvent which does not unduly adversely interfere with theintended processes can be employed and such solvents may include thoseheretofore commonly employed in known metal catalyzed processes.Increasing the dielectric constant or polarity of a solvent maygenerally tend to favor increased reaction rates. Of course, mixtures ofone or more different solvents may be employed if desired. It is obviousthat the amount of solvent employed is not critical to the subjectinvention and need only be that amount sufficient to provide thereaction medium with the particular metal concentration desired for agiven process. In general, the amount of solvent when employed may rangefrom about 5 percent by weight up to about 99 percent by weight or morebased on the total weight of the reaction mixture starting materials.

The processes of this invention are useful for preparing substituted andunsubstituted optically active and non-optically active compounds.Illustrative compounds prepared by the processes of this inventioninclude, for example, substituted and unsubstituted alcohols or phenols;amines; amides; ethers or epoxides; esters; ketones; aldehydes; andnitrites. Illustrative of suitable optically active and non-opticallyactive compounds which can be prepared by the processes of thisinvention (including starting material compounds as describedhereinabove) include those permissible compounds which are described inKirk-Othmer, Encyclopedia of Chemical Technology, Fourth Edition, 1996,the pertinent portions of which are incorporated herein by reference,and The Merck Index, An Encyclopedia of Chemicals, Drugs andBiologicals, Eleventh Edition, 1989, the pertinent portions of which areincorporated herein by reference.

The desired products of this invention may be recovered in anyconventional manner and one or more separators or separation zones maybe employed in any given process to recover the desired reaction productfrom its crude reaction product fluid. Suitable separation methodsinclude, for example, solvent extraction, crystallization, distillation,vaporization, wiped film evaporation, falling film evaporation and thelike. It may be desired to remove the products from the crude reactionmixture as they are formed through the use of trapping agents asdescribed in published Pat. Cooperation Treaty Pat. Application WO88/08835. A preferred method for separating the product mixtures fromthe other components of the crude reaction mixtures is by membraneseparation. Such membrane separation can be achieved as set out in U.S.Pat. No. 5,430,194 and copending U.S. patent application Ser. No.08/430,790, filed May 5, 1995, referred to above.

The processes of this invention may be carried out using, for example, afixed bed reactor, a fluid bed reactor, a continuous stirred tankreactor (CSTR) or a slurry reactor. The optimum size and shape of thecatalysts will depend on the type of reactor used. In general, for fluidbed reactors, a small, spherical catalyst particle is preferred for easyfluidization. With fixed bed reactors, larger catalyst particles arepreferred so the back pressure within the reactor is kept reasonablylow. The at least one reaction zone employed in this invention may be asingle vessel or may comprise two or more discrete vessels. The at leastone separation zone employed in this invention may be a single vessel ormay comprise two or more discrete vessels. The at least one buffertreatment zone employed in this invention may be a single vessel or maycomprise two or more discrete vessels. It should be understood that thereaction zone(s) and separation zone(s) employed herein may exist in thesame vessel or in different vessels. For example, reactive separationtechniques such as reactive distillation, reactive membrane separationand the like may occur in the reaction zone(s).

The processes of this invention can be conducted in a batch orcontinuous fashion, with recycle of unconsumed starting materials ifrequired. The reaction can be conducted in a single reaction zone or ina plurality of reaction zones, in series or in parallel or it may beconducted batchwise or continuously in an elongated tubular zone orseries of such zones. The materials of construction employed should beinert to the starting materials during the reaction and the fabricationof the equipment should be able to withstand the reaction temperaturesand pressures. Means to introduce and/or adjust the quantity of startingmaterials or ingredients introduced batchwise or continuously into thereaction zone during the course of the reaction can be convenientlyutilized in the processes especially to maintain the desired molar ratioof the starting materials. The reaction steps may be effected by theincremental addition of one of the starting materials to the other.Also, the reaction steps can be combined by the joint addition of thestarting materials. When complete conversion is not desired or notobtainable, the starting materials can be separated from the product,for example by distillation, and the starting materials then recycledback into the reaction zone.

The processes may be conducted in either glass lined, stainless steel orsimilar type reaction equipment. The reaction zone may be fitted withone or more internal and/or external heat exchanger(s) in order tocontrol undue temperature fluctuations, or to prevent any possible"runaway" reaction temperatures.

The processes of this invention may be conducted in one or more steps orstages. The exact number of reaction steps or stages will be governed bythe best compromise between capital costs and achieving high catalystselectivity, activity, lifetime and ease of operability, as well as theintrinsic reactivity of the starting materials in question and thestability of the starting materials and the desired reaction product tothe reaction conditions.

In an embodiment, the hydroformylation processes useful in thisinvention may be carried out in a multistaged reactor such as described,for example, in copending U.S. patent application Ser. No. 08/757,743,filed on an even date herewith, the disclosure of which is incorporatedherein by reference. Such multistaged reactors can be designed withinternal, physical barriers that create more than one theoreticalreactive stage per vessel. In effect, it is like having a number ofreactors inside a single continuous stirred tank reactor vessel.Multiple reactive stages within a single vessel is a cost effective wayof using the reactor vessel volume. It significantly reduces the numberof vessels that otherwise would be required to achieve the same results.Fewer vessels reduces the overall capital required and maintenanceconcerns with separate vessels and agitators.

Hydroformylation Processes

A preferred process useful in this invention is hydroformylation.Illustrative metal-organopolyphosphite ligand complex catalyzedhydroformylation processes which may experience such hydrolyticdegradation of the organopolyphosphite ligand and catalytic deactivationinclude such processes as described, for example, in U.S. Pat. Nos.4,148,830; 4,593,127; 4,769,498; 4,717,775; 4,774,361; 4,885,401;5,264,616; 5,288,918; 5,360,938; 5,364,950; and 5,491,266; thedisclosures of which are incorporated herein by reference. Accordingly,the hydroformylation processing techniques of this invention maycorrespond to any known processing techniques. Preferred processes arethose involving catalyst liquid recycle hydroformylation processes.

In general, such catalyst liquid recycle hydroformylation processesinvolve the production of aldehydes by reacting an olefinic unsaturatedcompound with carbon monoxide and hydrogen in the presence of ametal-organopolyphosphite ligand complex catalyst in a liquid mediumthat also contains an organic solvent for the catalyst and ligand.Preferably free organopolyphosphite ligand is also present in the liquidhydroformylation reaction medium. By "free organopolyphosphite ligand"is meant organopolyphosphite ligand that is not complexed with (tied toor bound to) the metal, e.g., metal atom, of the complex catalyst. Therecycle procedure generally involves withdrawing a portion of the liquidreaction medium containing the catalyst and aldehyde product from thehydroformylation reactor (i.e., reaction zone), either continuously orintermittently, and recovering the aldehyde product therefrom by use ofa composite membrane such as disclosed in U.S. Pat. No. 5,430,194 andcopending U.S. patent application Ser. No. 08/430,790, filed May 5,1995, the disclosures of which are incorporated herein by reference, orby the more conventional and preferred method of distilling it (i.e.,vaporization separation) in one or more stages under normal, reduced orelevated pressure, as appropriate, in a separate distillation zone, thenon-volatilized metal catalyst containing residue being recycled to thereaction zone as disclosed, for example, in U.S. Pat. No. 5,288,918.Condensation of the volatilized materials, and separation and furtherrecovery thereof, e.g., by further distillation, can be carried out inany conventional manner, the crude aldehyde product can be passed on forfurther purification and isomer separation, if desired, and anyrecovered reactants, e.g., olefinic starting material and syn gas, canbe recycled in any desired manner to the hydroformylation zone(reactor). The recovered metal catalyst containing raffinate of suchmembrane separation or recovered non-volatilized metal catalystcontaining residue of such vaporization separation can be recycled, tothe hydroformylation zone (reactor) in any conventional manner desired.

In a preferred embodiment, the hydroformylation reaction product fluidsemployable herein includes any fluid derived from any correspondinghydroformylation process that contains at least some amount of fourdifferent main ingredients or components, i.e., the aldehyde product, ametal-organopolyphosphite ligand complex catalyst, freeorganopolyphosphite ligand and an organic solubilizing agent for saidcatalyst and said free ligand, said ingredients corresponding to thoseemployed and/or produced by the hydroformylation process from whence thehydroformylation reaction mixture starting material may be derived. Itis to be understood that the hydroformylation reaction mixturecompositions employable herein can and normally will contain minoramounts of additional ingredients such as those which have either beendeliberately employed in the hydroformylation process or formed in situduring said process. Examples of such ingredients that can also bepresent include unreacted olefin starting material, carbon monoxide andhydrogen gases, and in situ formed type products, such as saturatedhydrocarbons and/or unreacted isomerized olefins corresponding to theolefin starting materials, and high boiling liquid aldehyde condensationbyproducts, as well as other inert co-solvent type materials orhydrocarbon additives, if employed.

The substituted or unsubstituted olefinic unsaturated starting materialreactants that may be employed in the hydroformylation processes of thisinvention include both optically active (prochiral and chiral) andnon-optically active (achiral) olefinic unsaturated compounds containingfrom 2 to 40, preferably 4 to 20, carbon atoms. Such olefinicunsaturated compounds can be terminally or internally unsaturated and beof straight-chain, branched chain or cyclic structures, as well asolefin mixtures, such as obtained from the oligomerization of propene,butene, isobutene, etc. (such as so called dimeric, trimeric ortetrameric propylene and the like, as disclosed, for example, in U. S.Pat. Nos. 4,518,809 and 4,528,403). Moreover, such olefin compounds mayfurther contain one or more ethylenic unsaturated groups, and of course,mixtures of two or more different olefinic unsaturated compounds may beemployed as the starting hydroformylation material if desired. Forexample, commercial alpha olefins containing four or more carbon atomsmay contain minor amounts of corresponding internal olefins and/or theircorresponding saturated hydrocarbon and that such commercial olefinsneed not necessarily be purified from same prior to beinghydroformylated. Illustrative mixtures of olefinic starting materialsthat can be employed in the hydroformylation reactions include, forexample, mixed butenes, e.g., Raffinate I and II. Further such olefinicunsaturated compounds and the corresponding aldehyde products derivedtherefrom may also contain one or more groups or substituents which donot unduly adversely affect the hydroformylation process or the processof this invention such as described, for example, in U. S. Pat. Nos.3,527,809, 4,769,498 and the like.

Most preferably the subject invention is especially useful for theproduction of non-optically active aldehydes, by hydroformylatingachiral alpha-olefins containing from 2 to 30, preferably 4 to 20,carbon atoms, and achiral internal olefins containing from 4 to 20carbon atoms as well as starting material mixtures of such alpha olefinsand internal olefins.

Illustrative alpha and internal olefins include, for example, ethylene,propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-nonene, 1-decene,1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene,1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene,2-butene, 2-methyl propene (isobutylene), 2-methylbutene, 2-pentene,2-hexene, 3-hexane, 2-heptene, 2-octene, cyclohexene, propylene dimers,propylene trimers, propylene tetramers, butadiene, piperylene, isoprene,2-ethyl-1-hexene, styrene, 4-methyl styrene, 4-isopropyl styrene,4-tert-butyl styrene, alpha-methyl styrene, 4-tert-butyl-alpha-methylstyrene, 1,3-diisopropenylbenzene, 3-phenyl-1-propene, 1,4-hexadiene,1,7-octadiene, 3-cyclohexyl-1-butene, and the like, as well as,1,3-dienes, butadiene, alkyl alkenoates, e.g., methyl pentenoate,alkenyl alkanoates, alkenyl alkyl ethers, alkenols, e.g., pentenols,alkenals, e.g., pentenals, and the like, such as allyl alcohol, allylbutyrate, hex-1-en-4-ol, oct-1-en-4-ol, vinyl acetate, allyl acetate,3-butenyl acetate, vinyl propionate, allyl propionate, methylmethacrylate, vinyl ethyl ether, vinyl methyl ether, allyl ethyl ether,n-propyl-7-octenoate, 3-butenenitrile, 5-hexenamide, eugenol,iso-eugenol, safrole, iso-safrole, anethol, 4-allylanisole, indene,limonene, beta-pinene, dicyclopentadiene, cyclooctadiene, camphene,linalool, and the like.

Prochiral and chiral olefins useful in the asymmetric hydroformylationthat can be employed to produce enantiomeric aldehyde mixtures that maybe encompassed by in this invention include those represented by theformula: ##STR24## wherein R₁, R₂, R₃ and R₄ are the same or different(provided R¹ is different from R₂ or R₃ is different from R₄) and areselected from hydrogen; alkyl; substituted alkyl, said substitutionbeing selected from dialkylamino such as benzylamino and dibenzylamino,alkoxy such as methoxy and ethoxy, acyloxy such as acetoxy, halo, nitro,nitrile, thio, carbonyl, carboxamide, carboxaldehyde, carboxyl,carboxylic ester; aryl including phenyl; substituted aryl includingphenyl, said substitution being selected from alkyl, amino includingalkylamino and dialkylamino such as benzylamino and dibenzylamino,hydroxy, alkoxy such as methoxy and ethoxy, acyloxy such as acetoxy,halo, nitrile, nitro, carboxyl, carboxaldehyde, carboxylic ester,carbonyl, and thio; acyloxy such as acetoxy; alkoxy such as methoxy andethoxy; amino including alkylamino and dialkylamino such as benzylaminoand dibenzylamino; acylamino and diacylamino such as acetylbenzylaminoand diacetylamino; nitro; carbonyl; nitrile; carboxyl; carboxamide;carboxaldehyde; carboxylic ester; and alkylmercapto such asmethylmercapto. It is understood that the prochiral and chiral olefinsof this definition also include molecules of the above general formulawhere the R groups are connected to form ring compounds, e.g.,3-methyl-1-cyclohexene, and the like.

Illustrative optically active or prochiral olefinic compounds useful inasymmetric hydroformylation include, for example, p-isobutylstyrene,2-vinyl-6-methoxy-2-naphthylene, 3-ethenylphenyl phenyl ketone,4-ethenylphenyl-2-thienylketone, 4-ethenyl-2-fluorobiphenyl,4-(1,3-dihydro-1-oxo-2H-isoindol-2-yl)styrene,2-ethenyl-5-benzoylthiophene, 3-ethenylphenyl phenyl ether,propenylbenzene, isobutyl-4-propenylbenzene, phenyl vinyl ether and thelike. Other olefinic compounds include substituted aryl ethylenes asdescribed, for example, in U.S. Pat. Nos. 4,329,507, 5,360,938 and5,491,266, the disclosures of which are incorporated herein byreference.

Illustrative of suitable substituted and unsubstituted olefinic startingmaterials include those permissible substituted and unsubstitutedolefinic compounds described in Kirk-Othmer, Encyclopedia of ChemicalTechnology, Fourth Edition, 1996, the pertinent portions of which areincorporated herein by reference.

As noted, the hydroformylation processes of this invention involve theuse of a metal-organopolyphosphite ligand complex catalyst as describedhereinabove. The hydroformylation catalysts may be in homogeneous orheterogeneous form during the reaction and/or during the productseparation. Of course mixtures of such catalysts can also be employed ifdesired. The amount of metal-organopolyphosphite ligand complex catalystpresent in the reaction medium of a given hydroformylation processencompassed by this invention need only be that minimum amount necessaryto provide the given metal concentration desired to be employed andwhich will furnish the basis for at least the catalytic amount of metalnecessary to catalyze the particular hydroformylation process involvedsuch as disclosed, for example, in the above-mentioned patents. Ingeneral, metal, e.g., rhodium, concentrations in the range of from about10 parts per million to about 1000 parts per million, calculated as freerhodium, in the hydroformylation reaction medium should be sufficientfor most processes, while it is generally preferred to employ from about10 to 500 parts per million of metal, e.g., rhodium, and more preferablyfrom 25 to 350 parts per million of metal, e.g., rhodium.

In addition to the metal-organopolyphosphite ligand complex catalyst,free organopolyphosphite ligand (i.e., ligand that is not complexed withthe metal) may also be present in the hydroformylation reaction medium.The free organopolyphosphite ligand may correspond to any of theabove-defined organopolyphosphite ligands employable herein. It ispreferred that the free organopolyphosphite ligand be the same as theorganopolyphosphite ligand of the metal-organopolyphosphite ligandcomplex catalyst employed. However, such ligands need not be the same inany given process. The hydroformylation process of this invention mayinvolve from about 0.1 moles or less to about 100 moles or higher, offree organopolypliosphite ligand per mole of metal in thehydroformylation reaction medium. Preferably the hydroformylationprocess of this invention is carried out in the presence of from about 1to about 50 moles of organopolyphosphite ligand, and more preferably fororganopolyphosphites from about 1.1 to about 4 moles oforganopolyphosphite ligand, per mole of metal present in the reactionmedium; said amounts of organopolyphosphite ligand being the sum of boththe amount of organopolyphosphite ligand that is bound (complexed) tothe metal present and the amount of free (non-complexed)organopolyphosphite ligand present. Since it is more preferred toproduce non-optically active aldehydes by hydroformylating achiralolefins, the more preferred organopolyphosphite ligands are achiral typeorganopolyphosphite ligands, especially those encompassed by Formula (I)above, and more preferably those of Formulas (II) and (V) above. Ofcourse, if desired, make-up or additional organopolyphosphite ligand canbe supplied to the reaction medium of the hydroformylation process atany time and in any suitable manner, e.g. to maintain a predeterminedlevel of free ligand in the reaction medium.

The reaction conditions of the hydroformylation processes encompassed bythis invention may include any suitable type hydroformylation conditionsheretofore employed for producing optically active and/or non-opticallyactive aldehydes. For instance, the total gas pressure of hydrogen,carbon monoxide and olefin starting compound of the hydroformylationprocess may range from about 1 to about 10,000 psia. In general,however, it is preferred that the process be operated at a total gaspressure of hydrogen, carbon monoxide and olefin starting compound ofless than about 2000 psia and more preferably less than about 500 psia.The minimum total pressure is limited predominately by the amount ofreactants necessary to obtain a desired rate of reaction. Morespecifically the carbon monoxide partial pressure of thehydroformylation process of this invention is preferable from about 1 toabout 1000 psia, and more preferably from about 3 to about 800 psia,while the hydrogen partial pressure is preferably about 5 to about 500psia and more preferably from about 10 to about 300 psia. In general H₂CO: molar ratio of gaseous hydrogen to carbon monoxide may range fromabout 1:10 to 100:1 or higher, the more preferred hydrogen to carbonmonoxide molar ratio being from about 1:10 to about 10:1. Further, thehydroformylation process may be conducted at a reaction temperature fromabout -25° C to about 200° C. In general hydroformylation reactiontemperatures of about 50° C. to about 120° C. are preferred for alltypes of olefinic starting materials. Of course it is to be understoodthat when non-optically active aldehyde products are desired, achiraltype olefin starting materials and organopolyphosphite ligands areemployed and when optically active aldehyde products are desiredprochiral or chiral type olefin starting materials andorganopolyphosphite ligands are employed. Of course, it is to be alsounderstood that the hydroformylation reaction conditions employed willbe governed by the type of aldehyde product desired.

The hydroformylation processes encompassed by this invention are alsoconducted in the presence of an organic solvent for themetal-organopolyphosphite ligand complex catalyst and freeorganopolyphosphite ligand. The solvent may also contain dissolved waterup to the saturation limit. Depending on the particular catalyst andreactants employed, suitable organic solvents include, for example,alcohols, alkanes, alkenes, alkynes, ethers, aldehydes, higher boilingaldehyde condensation byproducts, ketones, esters, amides, tertiaryamines, aromatics and the like. Any suitable solvent which does notunduly adversely interfere with the intended hydroformylation reactioncan be employed and such solvents may include those disclosed heretoforecommonly employed in known metal catalyzed hydroformylation reactions.Mixtures of one or more different solvents may be employed if desired.In general, with regard to the production of achiral (non-opticallyactive) aldehydes, it is preferred to employ aldehyde compoundscorresponding to the aldehyde products desired to be produced and/orhigher boiling aldehyde liquid condensation byproducts as the mainorganic solvents as is common in the art. Such aldehyde condensationbyproducts can also be preformed if desired and used accordingly.Illustrative preferred solvents employable in the production ofaldehydes include ketones (e.g. acetone and methylethyl ketone), esters(e.g. ethyl acetate), hydrocarbons (e.g. toluene), nitrohydrocarbons(e.g. nitrobenzene), ethers (e.g. tetrahydrofuran (THF) and sulfolane.Suitable solvents are disclosed in U.S. Pat. No. 5,312,996. The amountof solvent employed is not critical to the subject invention and needonly be that amount sufficient to solubilize the catalyst and freeligand of the hydroformylation reaction mixture to be treated. Ingeneral, the amount of solvent may range from about 5 percent by weightup to about 99 percent by weight or more based on the total weight ofthe hydroformylation reaction mixture starting material.

Accordingly illustrative non-optically active aldehyde products includee.g., propionaldehyde, n-butyraldehyde, isobutyraldehyde,n-valeraldehyde, 2-methyl 1-butyraldehyde, hexanal, hydroxyhexanal,2-methyl valeraldehyde, heptanal, 2-methyl 1-hexanal, octanal, 2-methyl1-heptanal, nonanal, 2-methyl-1-octanal, 2-ethyl 1-heptanal, 3-propyl1-hexanal, decanal, adipaldehyde, 2-methylglutaraldehyde,2-methyladipaldehyde, 3-methyladipaldehyde, 3-hydroxypropionaldehyde,6-hydroxyhexanal, alkenals, e.g., 2-, 3- and 4-pentenal, alkyl5-formylvalerate, 2-methyl-1-nonanal, undecanal, 2-methyl 1-decanal,dodecanal, 2-methyl 1-undecanal, tridecanal, 2-methyl 1-tridecanal,2-ethyl, 1-dodecanal, 3-propyl-1-undecanal, pentadecanal,2-methyl-1-tetradecanal, hexadecanal, 2-methyl-1-pentadecanal,heptadecanal, 2-methyl-1-hexadecanal, octadecanal,2-methyl-1-heptadecanal, nonodecanal, 2-methyl-1-octadecanal, 2-ethyl1-heptadecanal, 3-propyl-1-hexadecanal, eicosanal,2-methyl-1-nonadecanal, heneicosanal, 2-methyl-1-eicosanal, tricosanal,2-methyl-1-docosanal, tetracosanal, 2-methyl-1-tricosanal, pentacosanal,2-methyl-1-tetracosanal, 2-ethyl 1-tricosanal, 3-propyl-1-docosanal,heptacosanal, 2-methyl-1-octacosanal, nonacosanal,2-methyl-1-octacosanal, hentriacontanal, 2-methyl-1-triacontanal, andthe like.

Illustrative optically active aldehyde products include (enantiomeric)aldehyde compounds prepared by the asymmetric hydroformylation processof this invention such as, e.g. S-2-(p-isobutylphenyl)-propionaldehyde,S-2-(6-methoxy-2-naphthyl)propionaldehyde,S-2-(3-benzoylphenyl)-propionaldehyde,S-2-(p-thienoylphenyl)propionaldehyde,S-2-(3-fluoro-4-phenyl)phenylpropionaldehyde, S-2-4-(1,3-dihydro-1-oxo-2H-isoindol-2-yl)phenyl!propionaldehyde,S-2-(2-methylacetaldehyde)-5-benzoylthiophene and the like.

Illustrative of suitable substituted and unsubstituted aldehyde productsinclude those permissible substituted and unsubstituted aldehydecompounds described in Kirk-Othmer, Encyclopedia of Chemical Technology,Fourth Edition, 1996, the pertinent portions of which are incorporatedherein by reference.

As indicated above, it is generally preferred to carry out thehydroformylation processes of this invention in a continuous manner. Ingeneral, continuous hydroformylation processes are well known in the artand may involve: (a) hydroformylating the olefinic starting material(s)with carbon monoxide and hydrogen in a liquid homogeneous reactionmixture comprising a solvent, the metal-organopolyphosphite ligandcomplex catalyst, free organopolyphosphite ligand; (b) maintainingreaction temperature and pressure conditions favorable to thehydroformylation of the olefinic starting material(s); (c) supplyingmake-up quantities of the olefinic starting material(s), carbon monoxideand hydrogen to the reaction medium as those reactants are used up; and(d) recovering the desired aldehyde hydroformylation product(s) in anymanner desired. The continuous process can be carried out in a singlepass mode, i.e., wherein a vaporous mixture comprising unreactedolefinic starting material(s) and vaporized aldehyde product is removedfrom the liquid reaction mixture from whence the aldehyde product isrecovered and make-up olefinic starting material(s), carbon monoxide andhydrogen are supplied to the liquid reaction medium for the next singlepass without recycling the unreacted olefinic starting material(s). Suchtypes of recycle procedure are well known in the art and may involve theliquid recycling of the metal-organopolyphosphite complex catalyst fluidseparated from the desired aldehyde reaction product(s), such asdisclosed, for example, in U.S. Pat. No. 4,148,830 or a gas recycleprocedure such as disclosed, for example, in U.S. Pat. No. 4,247,486, aswell as a combination of both a liquid and gas recycle procedure ifdesired. The disclosures of said U.S. Pat. Nos. 4,148,830 and 4,247,486are incorporated herein by reference thereto. The most preferredhydroformylation process of this invention comprises a continuous liquidcatalyst recycle process. Suitable liquid catalyst recycle proceduresare disclosed, for example, in U.S. Pat. Nos. 4,668,651; 4,774,361;5,102,505 and 5,110,990.

In an embodiment of this invention, the aldehyde product mixtures may beseparated from the other components of the crude reaction mixtures inwhich the aldehyde mixtures are produced by any suitable method.Suitable separation methods include, for example, solvent extraction,phase separation, crystallization, distillation, vaporization, wipedfilm evaporation, falling film evaporation and the like. It may bedesired to remove the aldehyde products from the crude reaction mixtureas they are formed through the use of trapping agents as described inpublished Patent Cooperation Treaty Pat. Application WO 88/08835. Apreferred method for separating the aldehyde mixtures from the othercomponents of the crude reaction mixtures is by membrane separation.Such membrane separation can be achieved as set out in U.S. Pat. No.5,430,194 and copending U.S. patent application Ser. No. 08/430,790,filed May 5, 1995, referred to above.

As indicated above, at the conclusion of (or during) the process of thisinvention, the desired aldehydes may be recovered from the reactionmixtures used in the process of this invention. For example, therecovery techniques disclosed in U.S. Pat. Nos. 4,148,830 and 4,247,486can be used. For instance, in a continuous liquid catalyst recycleprocess the portion of the liquid reaction mixture (containing aldehydeproduct, catalyst, etc.), i.e., reaction product fluid, removed from thereaction zone can be passed to a separation zone, e.g.,vaporizer/separator, wherein the desired aldehyde product can beseparated via distillation, in one or more stages, under normal, reducedor elevated pressure, from the liquid reaction fluid, condensed andcollected in a product receiver, and further purified if desired. Theremaining non-volatilized catalyst containing liquid reaction mixturemay then be recycled back to the reaction zone as may if desired anyother volatile materials, e.g., unreacted olefin, together with anyhydrogen and carbon monoxide dissolved in the liquid reaction afterseparation thereof from the condensed aldehyde product, e.g., bydistillation in any conventional manner. In general, it is preferred toseparate the desired aldehydes from the catalyst-containing reactionmixture under reduced pressure and at low temperatures so as to avoidpossible degradation of the organopolyphosphite ligand and reactionproducts. When an alpha-mono-olefin reactant is also employed, thealdehyde derivative thereof can also be separated by the above methods.

More particularly, distillation and separation of the desired aldehydeproduct from the metal-organopolyphosphite complex catalyst containingreaction product fluid may take place at any suitable temperaturedesired. In general, it is recommended that such distillation take placeat relatively low temperatures, such as below 150° C., and morepreferably at a temperature in the range of from about 50° C. to about140° C. It is also generally recommended that such aldehyde distillationtake place under reduced pressure, e.g., a total gas pressure that issubstantially lower than the total gas pressure employed duringhydroformylation when low boiling aldehydes (e.g., C₄ to C₆) areinvolved or under vacuum when high boiling aldehydes (e.g. C₇ orgreater) are involved. For instance, a common practice is to subject theliquid reaction product medium removed from the hydroformylationreaction zone to a pressure reduction so as to volatilize a substantialportion of the unreacted gases dissolved in the liquid medium which nowcontains a much lower synthesis gas concentration than was present inthe hydroformylation reaction medium to the distillation zone, e.g.vaporizer/separator, wherein the desired aldehyde product is distilled.In general, distillation pressures ranging from vacuum pressures on upto total gas pressure of about 50 psig should be sufficient for mostpurposes.

Acid Removal Treatment

As indicated above, the reaction product fluids containing phosphorusacidic compounds may be treated in an acid removal zone with an acidremoval substance sufficient to remove at least some amount of thephosphorus acidic compounds from said reaction product fluid.Preferably, phosphorus acidic compounds can be removed from the reactionproduct fluid by (a) withdrawing from at least one reaction zone or atleast one separation zone at least a portion of a reaction product fluidderived from a hydroformylation process and which also containsphosphorus acidic compounds formed during said hydroformylation process,(b) treating in at least one acid removal zone at least a portion of thewithdrawn reaction product fluid derived from said hydroformylationprocess and which also contains phosphorus acidic compounds formedduring said hydroformylation process with an acid removal substancesufficient to remove at least some amount of the phosphorus acidiccompounds from said reaction product fluid, and (c) returning thetreated reaction product fluid to at least one reaction zone or at leastone separation zone.

In an embodiment of this invention, a means for preventing or minimizingligand degradation and catalyst deactivation and/or precipitation thatmay be useful in this invention involves carrying out the inventiondescribed and taught in copending U.S. patent application Ser. Nos.(08/756,501) and (08/753,505), both filed on an even date herewith, thedisclosures of which are incorporated herein by reference, whichcomprises using an aqueous buffer solution and optionally organicnitrogen compounds as disclosed therein.

For instance, said aqueous buffer solution invention comprises treatingat least a portion of a metal-organopolyphosphite ligand complexcatalyst containing reaction product fluid derived from saidhydroformylation process and which also contains phosphorus acidiccompounds formed during said hydroformylation process, with an aqueousbuffer solution in order to neutralize and remove at least some amountof the phosphorus acidic compounds from said reaction product fluid, andthen returning the treated reaction product fluid to thehydroformylation reaction zone or separation zone. Illustrativephosphorus acidic compounds include, for example, H₃ PO₃, aldehyde acidssuch as hydroxy alkyl phosphonic acids, H₃ PO₄ and the like. Saidtreatment of the metal-organopolyphosphite ligand complex catalystcontaining reaction product fluid with the aqueous buffer solution maybe conducted in any suitable manner or fashion desired that does notunduly adversely affect the basic hydroformylation process from whichsaid reaction product fluid was derived.

Thus, for example, the aqueous buffer solution may be used to treat allor part of a reaction medium of a continuous liquid catalyst recyclehydroformylation process that has been removed from the reaction zone atany time prior to or after separation of the aldehyde product therefrom.More preferably said aqueous buffer treatment involves treating all orpart of the reaction product fluid obtained after distillation of asmuch of the aldehyde product desired, e.g. prior to or during therecycling of said reaction product fluid to the reaction zone. Forinstance, a preferred mode would be to continuously pass all or part(e.g. a slip stream) of the recycled reaction product fluid that isbeing recycled to the reaction zone through a liquid extractorcontaining the aqueous buffer solution just before said catalystcontaining residue is to re-enter the reaction zone.

Thus it is to be understood that the metal-organopolyphosphite ligandcomplex catalyst containing reaction product fluid to be treated withthe aqueous buffer solution may contain in addition to the catalystcomplex and its organic solvent, aldehyde product, free phosphiteligand, unreacted olefin, and any other ingredient or additiveconsistent with the reaction medium of the hydroformylation process fromwhich said reaction product fluids are derived.

Typically maximum aqueous buffer solution concentrations are onlygoverned by practical considerations. As noted, treatment conditionssuch as temperature, pressure and contact time may also vary greatly andany suitable combination of such conditions may be employed herein. Ingeneral liquid temperatures ranging from about 20° C. to about 80° C.and preferably from about 25° C., to about 60° C. should be suitable formost instances, although lower or higher temperatures could be employedif desired. Normally the treatment is carried out under pressuresranging from ambient to reaction pressures and the contact time may varyfrom a matter of seconds or minutes to a few hours or more.

Moreover, success in removing phosphorus acidic compounds from thereaction product fluid may be determined by measuring the ratedegradation (consumption) of the organopolyphosphite ligand present inthe hydroformylation reaction medium. In addition as the neutralizationand extraction of phosphorus acidic compounds into the aqueous buffersolution proceeds, the pH of the buffer solution will decrease andbecome more and more acidic. When the buffer solution reaches anunacceptable acidity level it may simply be replaced with a new buffersolution.

The aqueous buffer solutions employable in this invention may compriseany suitable buffer mixture containing salts of oxyacids, the nature andproportions of which in the mixture, are such that the pH of theiraqueous solutions may range from 3 to 9, preferably from 4 to 8 and morepreferably from 4.5 to 7.5. In this context suitable buffer systems mayinclude mixtures of anions selected from the group consisting ofphosphate, carbonate, citrate and borate compounds and cations selectedfrom the group consisting of ammonium and alkali metals, e.g. sodium,potassium and the like. Such buffer systems and/or methods for theirpreparation are well known in the art.

Preferred buffer systems are phosphate buffers and citrate buffers, e.g.monobasic phosphate/dibasic phosphates of an alkali metal and citratesof an alkali metal. More preferred are buffer systems consisting ofmixtures of the monobasic phosphate and the dibasic phosphate of sodiumor potassium.

Optionally, an organic nitrogen compound may be added to thehydroformylation reaction product fluid to scavenge the acidichydrolysis byproducts formed upon hydrolysis of the organophosphiteligand, as taught, for example, in U.S. Pat. No. 4,567,306. Such organicnitrogen compounds may be used to react with and to neutralize theacidic compounds by forming conversion product salts therewith, therebypreventing the rhodium from complexing with the acidic hydrolysisbyproducts and thus helping to protect the activity of the metal, e.g.,rhodium, catalyst while it is present in the reaction zone underhydroformylation conditions. The choice of the organic nitrogen compoundfor this function is, in part, dictated by the desirability of using abasic material that is soluble in the reaction medium and does not tendto catalyze the formation of aldols and other condensation products at asignificant rate or to unduly react with the product aldehyde.

Such organic nitrogen compounds may contain from 2 to 30 carbon atoms,and preferably from 2 to 24 carbon atoms. Primary amines should beexcluded from use as said organic nitrogen compounds. Preferred organicnitrogen compounds should have a distribution coefficient that favorssolubility in the organic phase. In general more preferred organicnitrogen compounds useful for scavenging the phosphorus acidic compoundspresent in the hydroformylation reaction product fluid of this inventioninclude those having a pKa value within ±3 of the pH of the aqueousbuffer solution employed. Most preferably the pKa value of the organicnitrogen compound will be essentially about the same as the pH of theaqueous buffer solution employed. Of course it is to be understood thatwhile it may be preferred to employ only one such organic nitrogencompound at a time in any given hydroformylation process, if desired,mixtures of two or more different organic nitrogen compounds may also beemployed in any given processes.

Illustrative organic nitrogen compounds include e.g., trialkylamines,such as triethylamine, tri-n-propylamine, tri-n-butylamine,tri-iso-butylamine, tri-iso-propylamine, tri-n-hexylamine,tri-n-octylamine, dimethyl-iso-propylamine, dimethyl-hexadecylamine,methyl-di-n-octylamine, and the like, as well as substituted derivativesthereof containing one or more noninterfering substituents such ashydroxy groups, for example triethanolamine, N-methyl-di-ethanolamine,tris-(3-hydroxypropyl)-amine, and the like. Heterocyclic amines can alsobe used such as pyridine, picolines, lutidines, collidines,N-methylpiperidine, N-methylmorpholine, N-2'-hydroxyethylmorpholine,quinoline, iso-quinoline, quinoxaline, acridien, quinuclidine, as wellas, diazoles, triazole, diazine and triazine compounds, and the like.Also suitable for possible use are aromatic tertiary amines, such asN,N-dimethylaniline, N,N-diethylaniline, N,N-dimethyl-p-toluidine,N-methyldiphenylamine, N,N-dimethylbenzylamine,N,N-dimethyl-1-naphthylamine, and the like. Compounds containing two ormore amino groups, such as N,N,N',N'-tetramethylethylene diamine andtriethylene diamine (i.e. 1,4-diazabicyclo- 2,2,2!-octane) can also bementioned.

Preferred organic nitrogen compounds useful for scavenging thephosphorus acidic compounds present in the hydroformylation reactionproduct fluids of the this invention are heterocyclic compounds selectedfrom the group consisting of diazoles, triazoles, diazines andtriazines, such as those disclosed and employed in copending U.S. patentapplication Ser. No. (08/756,789), filed on an even date herewith, thedisclosure of which is incorporated herein by reference. For example,benzimidazole and benztriazole are preferred candidates for such use.

Illustrative of suitable organic nitrogen compounds include thosepermissible organic nitrogen compounds described in Kirk-Othmer,Encyclopedia of Chemical Technology, Fourth Edition, 1996, the pertinentportions of which are incorporated herein by reference.

The amount of organic nitrogen compound that may be present in thereaction product fluid for scavenging the phosphorus acidic compoundspresent in the hydroformylation reaction product fluids of the thisinvention is typically sufficient to provide a concentration of at leastabout 0.0001 moles of free organic nitrogen compound per liter ofreaction product fluid. In general the ratio of organic nitrogencompound to total organophosphite ligand (whether bound with rhodium orpresent as free organophosphite) is at least about 0.1:1 and even morepreferably at least about 0.5:1. The upper limit on the amount oforganic nitrogen compound employed is governed mainly only by economicalconsiderations. Organic nitrogen compound: organophosphite molar ratiosof at least about 1:1 up to about 5:1 should be sufficient for mostpurpose.

It is to be understood the organic nitrogen compound employed toscavenge said phosphorus acidic compounds need not be the same as theheterocyclic nitrogen compound employed to protect the metal catalystunder harsh conditions such as exist in the aldehydevaporizer-separator, as taught in copending U.S. patent application Ser.No. 08/756,789, referred to above. However, if said organic nitrogencompound and said heterocyclic nitrogen compound are desired to be thesame and perform both said functions in a given process, care should betaken to see that there will be a sufficient amount of the heterocyclicnitrogen compound present in the reaction medium to also provide thatamount of free heterocyclic nitrogen compound in the hydroformylationprocess, e.g., vaporizer-separator, that will allow both desiredfunctions to be achieved.

Accordingly the aqueous buffer solution treatment of this invention willnot only remove free phosphoric acidic compounds from themetal-organophosphite ligand complex catalyst containing reactionproduct fluids, the aqueous buffer solution also surprisingly removesthe phosphorus acidic material of the conversion product salt formed bythe use of the organic nitrogen compound scavenger when employed, i.e.,the phosphorus acid of said conversion product salt remains behind inthe aqueous buffer solution, while the treated reaction product fluid,along with the reactivated (free) organic nitrogen compound is returnedto the hydroformylation reaction zone.

Another problem that has been observed when organopolyphosphite ligandpromoted metal catalysts are employed in hydroformylation processes,e.g., continuous liquid catalyst recycle hydroformylation processes,that involve harsh conditions such as recovery of the aldehyde via avaporizer-separator, i.e., the slow loss in catalytic activity of thecatalysts is believed due at least in part to the harsh conditions suchas exist in a vaporizer employed in the separation and recovery of thealdehyde product from its reaction product fluid. For instance, it hasbeen found that when an organopolyphosphite promoted rhodium catalyst isplaced under harsh conditions such as high temperature and low carbonmonoxide partial pressure, that the catalyst deactivates at anaccelerated pace with time, due most likely to the formation of aninactive or less active rhodium species, which may also be susceptibleto precipitation under prolonged exposure to such harsh conditions. Suchevidence is also consistent with the view that the active catalyst whichunder hydroformylation conditions is believed to comprise a complex ofrhodium, organopolyphosphite, carbon monoxide and hydrogen, loses atleast some of its coordinated carbon monoxide ligand during exposure tosuch harsh conditions as encountered in vaporization, which provides aroute for the formation of catalytically inactive or less active rhodiumspecies. The means for preventing or minimizing such catalystdeactivation and/or precipitation involves carrying out the inventiondescribed and taught in copending U.S. patent application Ser. No.(08/756,789), referred to above, which comprises carrying out thehydroformylation process under conditions of low carbon monoxide partialpressure in the presence of a free heterocyclic nitrogen compound asdisclosed therein.

By way of further explanation it is believed the free heterocyclicnitrogen compound serves as a replacement ligand for the lost carbonmonoxide ligand thereby forming a neutral intermediate metal speciescomprising a complex of the metal, organopolyphosphite, the heterocyclicnitrogen compound and hydrogen during such harsh conditions, e.g.,vaporization separation, thereby preventing or minimizing the formationof any such above mentioned catalytic inactive or less active metalspecies. It is further theorized that the maintenance of catalyticactivity, or the minimization of its deactivation, throughout the courseof such continuous liquid recycle hydroformylation is due toregeneration of the active catalyst from said neutral intermediate metalspecies in the reactor (i.e. hydroformylation reaction zone) of theparticular hydroformylation process involved. It is believed that underthe higher syn gas pressure hydroformylation conditions in the reactor,the active catalyst complex comprising metal, e.g., rhodium,organopolyphosphite, carbon monoxide and hydrogen is regenerated as aresult of some of the carbon monoxide in the reactant syn gas replacingthe heterocyclic nitrogen ligand of the recycled neutral intermediaterhodium species. That is to say, carbon monoxide having a strongerligand affinity for rhodium, replaces the more weakly bondedheterocyclic nitrogen ligand of the recycled neutral intermediaterhodium species that was formed during vaporization separation asmentioned above, thereby reforming the active catalyst in thehydroformylation reaction zone.

Thus the possibility of metal catalyst deactivation due to such harshconditions is said to be minimized or prevented by carrying out suchdistillation of the desired aldehyde product from themetal-organopolyphosphite catalyst containing reaction product fluids inthe added presence of a free heterocyclic nitrogen compound having afive or six membered heterocyclic ring consisting of 2 to 5 carbon atomsand from 2 to 3 nitrogen atoms, at least one of said nitrogen atomscontaining a double bond. Such free heterocyclic nitrogen compounds maybe selected from the class consisting of diazole, triazole, diazine, andtriazine compounds, such as, e.g., benzimidazole or benzotriazole, andthe like. The term "free" as it applies to said heterocyclic nitrogencompounds is employed therein to exclude any acid salts of suchheterocyclic nitrogen compounds, i.e., salt compounds formed by thereaction of any phosphorus acidic compound present in thehydroformylation reaction product fluids with such free heterocyclicnitrogen compounds as discussed herein above.

It is to be understood that while it may be preferred to employ only onefree heterocyclic nitrogen compound at a time in any givenhydroformylation process, if desired, mixtures of two or more differentfree heterocyclic nitrogen compounds may also be employed in any givenprocess. Moreover the amount of such free heterocyclic nitrogencompounds present during harsh conditions, e.g., the vaporizationprocedure, need only be that minimum amount necessary to furnish thebasis for at least some minimization of such catalyst deactivation asmight be found to occur as a result of carrying out an identical metalcatalyzed liquid recycle hydroformylation process under essentially thesame conditions, in the absence of any free heterocyclic nitrogencompound during vaporization separation of the aldehyde product. Amountsof such free heterocyclic nitrogen compounds ranging from about 0.01 upto about 10 weight percent, or higher if desired, based on the totalweight of the hydroformylation reaction product fluid to be distilledshould be sufficient for most purposes.

An alternate method of transferring acidity from the hydroformylationreaction product fluid to an aqueous fraction is through theintermediate use of a heterocyclic amine which has a fluorocarbon orsilicone side chain of sufficient size that it is immiscible in both thehydroformylation reaction product fluid and in the aqueous fraction. Theheterocyclic amine may first be contacted with the hydroformylationreaction product fluid where the acidity present in the reaction productfluid will be transferred to the nitrogen of the heterocyclic amine.This heterocyclic amine layer may then be decanted or otherwiseseparated from the reaction product fluid before contacting it with theaqueous fraction where it again would exist as a separate phase. Theheterocyclic amine layer may then be returned to contact thehydroformylation reaction product fluid.

Another means for preventing or minimizing ligand degradation andcatalyst deactivation and/or precipitation that may be useful in thisinvention involves carrying out the invention described and taught incopending U.S. patent application Ser. Nos. (08/753,504) and(08/753,503), both filed on an even date herewith, the disclosures ofwhich are incorporated herein by reference, which comprises using waterand optionally organic nitrogen compounds as disclosed therein.

For instance, it has been found that hydrolytic decomposition andrhodium catalyst deactivation as discussed herein can be prevented orlessened by treating at least a portion of the reaction product fluidderived from the hydroformylation process and which also containsphosphorus acidic compounds formed during the hydroformylation processwith water sufficient to remove at least some amount of the phosphorusacidic compounds from the reaction product fluid. Although both waterand acid are factors in the hydrolysis of organophosphite ligands, ithas been surprisingly discovered that hydroformylation reaction systemsare more tolerant of higher levels of water than higher levels of acid.Thus, the water can surprisingly be used to remove acid and decrease therate of loss of organophosphite ligand by hydrolysis.

Yet another means for preventing or minimizing ligand degradation andcatalyst deactivation and/or precipitation that may be useful in thisinvention involves carrying out the invention described and taught incopending U.S. patent application Ser. Nos. (D-17652) and (08/756,786),both filed on an even date herewith, the disclosures of which areincorporated herein by reference, which comprises using water inconjunction with acid removal substances and optionally organic nitrogencompounds as disclosed therein.

For instance, it has been found that hydrolytic decomposition andrhodium catalyst deactivation as discussed herein can be prevented orlessened by treating at least a portion of the reaction product fluidderived from the hydroformylation process and which also containsphosphorus acidic compounds formed during said hydroformylation processwith water in conjunction with one or more acid removal substances,e.g., oxides, hydroxides, carbonates, bicarbonates and carboxylates ofGroup 2, 11 and 12 metals, sufficient to remove at least some amount ofthe phosphorus acidic compounds from said reaction product fluid.Because metal salt contaminants, e.g., iron, zinc, calcium salts and thelike, in a hydroformylation reaction product fluid undesirably promotethe self condensation of aldehydes, an advantage is that one can use theacidity removing capability of certain acid removal substances withminimal transfer of metal salts to the hydroformylation reaction productfluid.

A further means for preventing or minimizing ligand degradation andcatalyst deactivation and/or precipitation that may be useful in thisinvention involves carrying out the invention described and taught incopending U.S. patent application Ser. Nos. (08/756,482) and(08/756,788), both filed on an even date herewith, the disclosures ofwhich are incorporated herein by reference, which comprises using ionexchange resins and optionally organic nitrogen compounds as disclosedtherein.

For instance, it has been found that hydrolytic decomposition andrhodium catalyst deactivation as discussed herein can be prevented orlessened by (a) treating in at least one scrubber zone at least aportion of said reaction product fluid derived from saidhydroformylation process and which also contains phosphorus acidiccompounds formed during said hydroformylation process with watersufficient to remove at least some amount of the phosphorus acidiccompounds from said reaction product fluid and (b) treating in at leastone ion exchange zone at least a portion of the water which containsphosphorus acidic compounds removed from said reaction product fluidwith one or more ion exchange resins sufficient to remove at least someamount of the phosphorus acidic compounds from said water. Becausepassing a hydroformylation reaction product fluid directly through anion exchange resin can cause rhodium precipitation on the ion exchangeresin surface and pores, thereby causing process complications, anadvantage is that one can use the acidity removing capability of ionexchange resins with essentially no loss of rhodium.

Other means for removing phosphorus acidic compounds from the reactionproduct fluids of this invention may be employed if desired. Thisinvention is not intended to be limited in any manner by the permissiblemeans for removing phosphorus acidic compounds from the reaction productfluids.

The processes of this invention may involve reacting one or morereactants in the presence of a metal-organopolyphosphite ligand complexcatalyst and optionally free organopolyphosphite ligand, and an amountof a sterically hindered organophosphorus ligand different from theorganopolyphosphite ligand of said metal-organopolyphosphite ligandcomplex catalyst, to produce one or more products, wherein saidsterically hindered organophosphorus ligand (i) has a coordinationstrength with respect to the metal of said metal-organopolyphosphiteligand complex catalyst less than the organopolyphosphite ligand of saidmetal-organopolyphosphite ligand complex catalyst, (ii) when complexedwith the metal to form a metal-sterically hindered organophosphorusligand complex catalyst, enables a reaction rate of at least 25 percentof the reaction rate enabled by the organopolyphosphite ligand of saidmetal-organopolyphosphite ligand complex catalyst, (iii) optionally hasa coordination strength with respect to the metal of saidmetal-organopolyphosphite ligand complex catalyst greater than carbonmonoxide, and (iv) optionally when complexed with the metal to form ametal-sterically hindered organophosphorus ligand complex catalyst,enables a normal:branched product isomer ratio lower than thenormal:branched product isomer ratio enabled by the organopolyphosphiteligand of said metal-organopolyphosphite ligand complex catalyst. See,for example, copending U.S. patent application Ser. Nos. (08/756,500)and (08/756,741), both filed on an even date herewith, the disclosuresof which are incorporated herein by reference.

For purposes of this invention, the term "hydrocarbon" is contemplatedto include all permissible compounds having at least one hydrogen andone carbon atom. Such permissible compounds may also have one or moreheteroatoms. In a broad aspect, the permissible hydrocarbons includeacyclic (with or without heteroatoms) and cyclic, branched andunbranched, carbocyclic and heterocyclic, aromatic and nonaromaticorganic compounds which can be substituted or unsubstituted.

As used herein, the term "substituted" is contemplated to include allpermissible substituents of organic compounds unless otherwiseindicated. In a broad aspect, the permissible substituents includeacyclic and cyclic, branched and unbranched, carbocyclic andheterocyclic, aromatic and nonaromatic substituents of organiccompounds. Illustrative substituents include, for example, alkyl,alkyloxy, aryl, aryloxy, hydroxy, hydroxyalkyl, amino, aminoalkyl,halogen and the like in which the number of carbons can range from 1 toabout 20 or more, preferably from 1 to about 12. The permissiblesubstituents can be one or more and the same or different forappropriate organic compounds. This invention is not intended to belimited in any manner by the permissible substituents of organiccompounds.

Certain of the following examples are provided to further illustratethis invention.

EXAMPLES 1-17

In a continuous catalyst liquid recycle manner, a mixed olefin startingmaterial of butene-1 and butene-2 (cis and trans) was hydroformylated.The liquid recycle reactor system employed contained from one to threeone-liter stainless steel stirred tank reactors, combined in series,each containing a vertically mounted agitator and a circular tubularsparger near the bottom of the reactor for feeding the olefin and/or syngas. The sparger contained a plurality of holes of sufficient size toprovide the desired gas flow into the liquid body. The reactors werejacketed with a silicone oil shell as means of bringing the contents ofthe reactors up to reaction temperature. All reactors contained internalcooling coils for controlling the reaction temperature. The reactorswere connected via a line to transfer any unreacted gases to thesubsequent reactor and were further connected via a line so that aportion of the liquid reaction solution containing aldehyde product andcatalyst from an upstream reactor could be purged into the subsequentreactor wherein unreacted olefin from the previous reactor can befurther hydroformylated. Each reactor also contained a pneumatic liquidlevel controller for automatic control of the liquid levels in thereactors. The first reactor further contained a line for introducing theolefin and syn gas through the sparger, while make up syn gas was addedto subsequent reactors via the same transfer line carrying the unreactedgases from the previous reactor. The final reactor in the series alsocontained a blow-off vent for removal of the unreacted gases. A linefrom the bottom of the final reactor was connected to the top of avaporizer so that a portion of the liquid reaction solution could bepumped from the final reactor to the vaporizer. Vaporized aldehyde wasdisengaged from the non-volatile components of the liquid reactionsolution in the gas-liquid separator part of the vaporizer. In someinstances, unreacted olefin was stripped from the liquid catalystproduct or the condensed aldehyde product and returned to the firstreactor in the series.

The hydroformylation reaction was conducted by charging about 1 liter ofa catalyst precursor solution of rhodium dicarbonyl acetylacetonatesufficient to achieve about 300 to 100 ppm rhodium in the operatingreactor solution, about 1.0 weight percent of Ligand D (as identifiedherein) (about 3 mole equivalents of ligand per mole of rhodium), andthe balance being C5 aldehyde and another heavier solvent (C5 trimer,Texanol®, or tetraglyme) to each reactor. The reactor system was thenpurged with nitrogen to remove any oxygen present. Then about 100 psignitrogen pressure was put on both reactors and the reactors heated totheir reaction temperatures given in Table A below. Controlled flows ofpurified hydrogen, carbon monoxide and a mixed olefin starting materialof butene-1 and butene-2 (cis and trans) were fed through the spargerinto the bottom of reactor 1 and the reactor pressures increased toachieve the partial pressures given in Table A. As the liquid level in areactor started to increase as a result of liquid aldehyde productformation a portion of the liquid reaction solution of the reactor waspumped into the subsequent reactor at a rate sufficient to maintain aconstant liquid level in the reactor. If the reactor was the finalreactor in the series, a portion of the liquid reaction solution waspumped to the vaporizer/separator at a rate sufficient to maintain aconstant liquid level in that reactor. Blow-off gas from the finalreactor was analyzed and measured. A controlled flow of make-up syn gas(CO and H2) was added to the reactors in order to maintain their desiredpartial pressure in those reactors. The operating pressures and reactiontemperatures were maintained throughout the hydroformylation. The liquidreaction product solution from the final reactor was subjected to anincreased temperature and decreased pressure sufficient to vaporize thealdehyde product from the liquid reaction solution. Typical conditionsrequired for the separation were from 90° C. to 115° C. and from 20 to 2psia. The vaporized product was condensed and collected in a productreceiver. The remaining non-volatilized catalyst containing liquidreaction solution was pumped to vessel means to contact the solutionwith the aqueous buffer identified in Table A. Experiments where either1,2-Epoxydodecane or 3,4-Epoxycyclohexylmethyl3,4-epoxycyclohexanecarboxylate resin was used were not treated with theaqueous buffer solution, but pumped directly back to the first reactorin series.

A C5 aldehyde catalyst solution containing 240 parts per million ofrhodium, 6 grams/liter of Ligand D, 1,2-epoxydodecane (0.6 grams) wasadded on the third day and each subsequent third day of the run. Thecatalyst solution throughout was contacted with carbon monoxide,hydrogen, and mixed butenes at partial pressures of 84, 89 and 41 psi,respectively all at a reactor temperature of 85° C. The product wasremoved continuously by means of an external vaporizer. Ligand Dconcentration was determined/monitored by ³¹ P NMR. An average ligandusage rate of 0.1 grams/liter/day was observed (Example 1 in Table A).Other runs were conducted in a similar manner and the results are givenin Table A (Examples 2-7).

A C5 aldehyde catalyst solution containing 240 parts per million ofrhodium and 6 grams/liter of Ligand D was contacted with carbonmonoxide, hydrogen, and mixed butenes at partial pressures of 40, 39 and24 psi, respectively all at a reactor temperature of 75° C. The productwas removed continuously by means of external vaporizer and theconcentrated catalyst solution passed through a 0.1M pH7 aqueous Na₂HPO₄ /NaH₂ PO₄ buffer solution prior to returning the concentratedcatalyst to the hydroformylation reactor. Ligand D concentration wasdetermined/monitored by ³¹ p NMR. An average ligand usage rate of 0.34grams/liter/day was observed (Table A--Example 15). Experiments 8-17 inTable A were all run under nominally the same conditions except the"topped-up" Ligand D concentration was varied throughout the run.

                  TABLE A                                                         ______________________________________                                                     React.               Initial                                                                            Usage                                       Acid    Temp    Partial Pressures, psi                                                                      L!  Rate                                   Ex.  Control °C.                                                                            CO    H.sub.2                                                                            C.sub.4 H.sub.8                                                                     G/L  G/L/Day                            ______________________________________                                        1    DDE.sup.a                                                                             85      84    89   41    6    0.10                               2    ERL-    85      90    90   49    4.2  0.07                                    4221.sup.b                                                               3    DDE.sup.a                                                                             85      74    77   55    6    0.12                               4    DDE.sup.a                                                                             85      89    97   30    8    0.09                               5    DDE.sup.a                                                                             85      84    88   38    6    0.11                               6    DDE.sup.a                                                                             75      38    30   32    6    0.08                               7    DDE.sup.a                                                                             75      40    37   16    6    0.1                                8    Extrac  75      40    39   24    4    0.37                                    tor.sup.c                                                                9    Extrac  75      40    39   24    2    0.27                                    tor.sup.c                                                                10   Extrac  75      40    39   24    3    0.13                                    tor.sup.c                                                                11   Extrac  75      40    39   24    5    0.37                                    tor.sup.c                                                                12   Extrac  75      40    39   24    1.67 0.1                                     tor.sup.c                                                                13   Extrac  75      40    39   24    2    0.13                                    tor.sup.c                                                                14   Extrac  75      40    39   24    0.67 0.13                                    tor.sup.c                                                                15   Extrac  75      40    39   24    6    0.34                                    tor.sup.c                                                                16   Extrac  75      40    39   24    2    0.29                                    tor.sup.c                                                                17   Extrac  75      40    39   24    2    0.11                                    tor.sup.c                                                                ______________________________________                                         .sup.a 1,2Epoxydodecane                                                       .sup.b 3,4Epoxycyclohexylmethyl 3,4epoxycyclohexanecarboxylate resin          .sup.c An 0.1M aqueous pH7 Na.sub.2 HPO.sub.4 /NaH.sub.2 PO.sub.4 buffer      solution                                                                 

FIG. 1 is a graphical representation of free ligand concentration(grams/liter) versus average ligand usage (grams/liter/day) based on theexperimental data set out in Table A above.

Examples 18 to 22 illustrate the in situ buffering effect of nitrogencontaining additives such as benzimidazole and the ability of theseadditives to transfer the acidity to an aqueous buffer solution.

EXAMPLE 18

This control example illustrates the stability of Ligand D (asidentified herein) in a solution containing 200 parts per million ofrhodium, and 0.39 percent by weight of Ligand D in butyraldehydecontaining aldehyde dimer and trimer in the absence of added acid orbenzimidazole.

To a clean, dry 25 milliliter vial was added 12 grams of thebutyraldehyde solution mentioned above. Samples were analyzed for LigandD using High Performance Liquid Chromatography after 24 and 72 hours.The weight percent of Ligand D was determined by High Performance LiquidChromatography relative to a calibration curve. No change in theconcentration of Ligand D was observed after either 24 or 72 hours.

EXAMPLE 19

This Example is similar to Example 18 except that phosphorus acid wasadded to simulate the type of acid that might be formed duringhydrolysis of an organophosphite.

The procedure for Example 18 was repeated with the modification ofadding 0.017 grams of phosphorous acid (H₃ PO₃) to the 12 gram solution.After 24 hours the concentration of Ligand D had decreased from 0.39 to0.12 percent by weight; after 72 hours the concentration of Ligand D haddecreased to 0.04 percent by weight. This data shows that strong acidscatalyze the decomposition of Ligand D.

EXAMPLE 20

This Example is similar to Example 18 except that both phosphorus acidand benzimidazole were added.

The procedure for Example 18 was repeated with the modification ofadding 0.018 grams of phosphorous acid and 0.0337 grams of benzimidazoleto the solution. No decomposition of Ligand D was observed after either24 or 72 hours. This shows that the addition of benzimidazoleeffectively buffers the effect of the strong acid and thereby preventsthe rapid decomposition of Ligand D.

EXAMPLE21

This example shows that an aqueous buffer can recover the acidity fromthe nitrogen base in situ buffer and allow the nitrogen base topartition into the organic phase, where it can be recycled to thehydroformylation zone.

Solid (benzimidazole)(H₃ PO₄) was prepared by placing 1.18 grams (10mmole) of benzimidazole in a 250 milliliter beaker and dissolving thebenzimidazole in 30 milliliters of tetrahydrofuran. To this solution wasslowly added 0.5 grams of 86 percent by weight of phosphoric acid (H₃PO₄). Upon addition of the acid a precipitate formed. The precipitatewas collected on a sintered glass frit and washed with tetrahydrofuran.The resulting solid was air-dried with the application of vacuum andused without any further purification. 0.109 grams (0.504 mmole) of thewater-soluble (benzimidazole)(H₃ PO₄) solid prepared in the previousstep was dissolved in 10 grams of 0.1M pH 7 sodium phosphate buffersolution. The resulting solution was extracted with 10 grams ofvaleraldehyde. The organic layer was then separated from the aqueouslayer using a separatory funnel. The volatile components were thenremoved from the organic layer by distillation at 100° C. to yield asolid. The solid was identical to authentic benzimidazole as shown bythin layer chromatography utilizing a 1:1 by volume mixture ofchloroform and acetone as the eluent and silica as the stationary phase.Based on recovery of the solid, benzimidazole was completely transferredto the organic phase.

This data shows that an organic soluble nitrogen base which exists as astrong acid salt can be regenerated by contact with an aqueous bufferand returned to the organic phase.

EXAMPLE 22

This example shows that a buffer solution is effective at neutralizingan organic soluble salt of a weak base and strong acid thus allowing thebase to return to the organic phase and effectively removing the acidfrom the organic phase.

A butyraldehyde solution was prepared containing 1.0 percent by weightof benzotriazole. The solution was then analyzed by Gas Chromatographyfor benzotriazole content to serve as a reference sample. To thesolution prepared in the previous step was added 0.25 mole equivalentsof phosphorous acid (H₃ PO₃). In a one pint glass bottle was added 50grams of the butyraldehyde solution containing benzotriazole and 50grams of a pH 7, 0.2 molar sodium phosphate buffer solution. The mixturewas stirred for 15 minutes and then transferred to a separatory funnel.The aqueous layer was then separated from the aldehyde layer. Theaqueous layer was analyzed for H₃ PO₃ content by Ion Chromatography. Thealdehyde layer was analyzed for benzotriazole content by GasChromatography and H₃ PO₃ content by Ion Chromatography. The H₃ PO₃ wasfound to be completely transferred into the aqueous layer. Completereturn of benzotriazole to the butyraldehyde layer was also found.

This data shows that an organic soluble salt of a weak base and strongacid can be completely neutralized by contacting the organic phase withan aqueous buffer solution and that the free base is thereby returned tothe organic phase.

Although the invention has been illustrated by certain of the precedingexamples, it is not to be construed as being limited thereby; butrather, the invention encompasses the generic area as hereinbeforedisclosed. Various modifications and embodiments can be made withoutdeparting from the spirit and scope thereof.

We claim:
 1. A process which comprises reacting one or more reactants inthe presence of a metal-organopolyphosphite ligand complex catalyst toproduce a reaction product fluid comprising one or more products,wherein said process is conducted at a free organopolyphosphite ligandconcentration of from 0 to about 8 grams per liter of reaction productfluid; and treating at least a portion of said reaction product fluidwhich also contains phosphorus acidic compounds formed during saidprocess with an acid removal substance sufficient to remove at leastsome amount of the phosphorus acidic compounds from said reactionproduct fluid.
 2. A process which comprises reacting one or morereactants in the presence of a metal-organopolyphosphite ligand complexcatalyst to produce a reaction product fluid comprising one or moreproducts, wherein said process is conducted (a) at a freeorganopolyphosphite ligand concentration of from 0 to about 8 grams perliter of reaction product fluid and (b) at a reaction zone and/orseparator zone residence time sufficient to prevent and/or lessenhydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst;and treating at least a portion of said reaction product fluid whichalso contains phosphorus acidic compounds formed during said processwith an acid removal substance sufficient to remove at least some amountof the phosphorus acidic compounds from said reaction product fluid. 3.An improved process for producing one or more products which comprises(i) reacting in at least one reaction zone one or more reactants in thepresence of a metal-organopolyphosphite ligand complex catalyst toproduce a reaction product fluid comprising one or more products and(ii) separating in at least one separation zone or in said at least onereaction zone the one or more products from said reaction product fluid,the improvement comprising preventing and/or lessening hydrolyticdegradation of the organopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst by conducting saidprocess (a) at a free organopolyphosphite ligand concentration of from 0to about 8 grams per liter of reaction product fluid, and (b) at areaction zone and/or separator zone residence time sufficient to preventand/or lessen hydrolytic degradation of the organopolyphosphite ligandand deactivation of the metal-organopolyphosphite ligand complexcatalyst; and by treating in at least one acid removal zone at least aportion of said reaction product fluid derived from said process andwhich also contains phosphorus acidic compounds formed during saidprocess with an acid removal substance sufficient to remove at leastsome amount of the phosphorus acidic compounds from said reactionproduct fluid.
 4. An improved process for producing one or more productswhich comprises (i) reacting in at least one reaction zone one or morereactants in the presence of a metal-organopolyphosphite ligand complexcatalyst to produce a reaction product fluid comprising one or moreproducts and (ii) separating in at least one separation zone or in saidat least one reaction zone the one or more products from said reactionproduct fluid, the improvement comprising preventing and/or lesseninghydrolytic degradation of the organopolyphosphite ligand anddeactivation of the metal-organopolyphosphite ligand complex catalyst byconducting said process (a) at a free organopolyphosphite ligandconcentration of from 0 to about 8 grams per liter of reaction productfluid, and (b) at a reaction zone and/or separator zone residence timesufficient to prevent and/or lessen hydrolytic degradation of theorganopolyphosphite ligand and deactivation of themetal-organopolyphosphite ligand complex catalyst; and by removingphosphorus acidic compounds from said reaction product fluid derivedfrom said process by (a) withdrawing from said at least one reactionzone or said at least one separation zone at least a portion of areaction product fluid derived from said process and which also containsphosphorus acidic compounds formed during said process, (b) treating inat least one acid removal zone at least a portion of the withdrawnreaction product fluid derived from said process and which also containsphosphorus acidic compounds formed during said process with an acidremoval substance sufficient to remove at least some amount of thephosphorus acidic compounds from said reaction product fluid, and (c)returning the treated reaction product fluid to said at least onereaction zone or said at least one separation zone.
 5. The process ofclaim 1 which comprises a hydroformylation, hydroacylation(intramolecular and intermolecular), hydrocyanation, hydroamidation,hydroesterification, aminolysis, alcoholysis, carbonylation,isomerization or transfer hydrogenation process.
 6. The process of claim1 wherein the free organopolyphosphite ligand concentration is fromabout 0.1 moles or less to about 4 moles of organopolyphosphite ligandper mole of metal.
 7. The process of claim 1 wherein the freeorganopolyphosphite ligand concentration is such that said process canbe operated below the threshold for autocatalytic hydrolysis of theorganopolyphosphite ligand.
 8. The process of claim 1 wherein saidmetal-organopolyphosphite ligand complex catalyst is homogeneous orheterogeneous.
 9. The process of claim 1 wherein said reaction productfluid contains a homogeneous or heterogeneous metal-organopolyphosphiteligand complex catalyst or at least a portion of said reaction productfluid contacts a fixed heterogeneous metal-organopolyphosphite ligandcomplex catalyst during said hydroformylation process.
 10. The processof claim 1 wherein said metal-organopolyphosphite ligand complexcatalyst comprises rhodium complexed with an organopolyphosphite ligandrepresented by the formula: ##STR25## wherein X represents a substitutedor unsubstituted n-valent organic bridging radical containing from 2 to40 carbon atoms, each R¹ is the same or different and represents adivalent organic radical containing from 4 to 40 carbon atoms, each R²is the same or different and represents a substituted or unsubstitutedmonovalent hydrocarbon radical containing from 1 to 24 carbon atoms,wherein a and b can be the same or different and each have a value of 0to 6, with the proviso that the sum of a+b is 2 to 6 and n equals a+b.11. The process of claim 10 wherein said metal-organopolyphosphiteligand complex catalyst comprises rhodium complexed with anorganopolyphosphite ligand having the formula selected from: ##STR26##wherein X represents a substituted or unsubstituted divalent hydrocarbonbridging radical containing from 2 to 40 carbon atoms, each R¹ is thesame or different and represents a divalent hydrocarbon radicalcontaining from 4 to 40 carbon atoms, and each R² is the same ordifferent and represents a substituted or unsubstituted monovalenthydrocarbon radical containing from 1 to 24 carbon atoms.
 12. Theprocess of claim 10 wherein said metal-organopolyphosphite ligandcomplex catalyst comprises rhodium complexed with an organopolyphosphiteligand having the formula selected from: ##STR27## wherein X representsa substituted or unsubstituted divalent hydrocarbon bridging radicalcontaining from 2 to 40 carbon atoms, R¹ is a divalent hydrocarbonradical containing from 4 to 40 carbon atoms, each R² is the same ordifferent and represents a substituted or unsubstituted monovalenthydrocarbon radical containing from 1 to 24 carbon atoms, each Ar is thesame or different and represents a substituted or unsubstituted arylradical, each y is the same or different and is a value of 0 or 1, Qrepresents a divalent bridging group selected from --C(R³)₂ --, --O--,--S--, --NR⁴ --, Si(R⁵)₂ --and --CO--, wherein each R³ is the same ordifferent and represents hydrogen, alkyl radicals having from 1 to 12carbon atoms, phenyl, tolyl, and anisyl, R⁴ represents hydrogen or amethyl radical, each R⁵ is the same or different and represents hydrogenor a methyl radical, and m is a value of 0 or
 1. 13. The process ofclaim 1 wherein said free organopolyphosphite ligand is represented bythe formula: ##STR28## wherein X represents a substituted orunsubstituted n-valent organic bridging radical containing from 2 to 40carbon atoms, each R¹ is the same or different and represents a divalentorganic radical containing from 4 to 40 carbon atoms, each R² is thesame or different and represents a substituted or unsubstitutedmonovalent hydrocarbon radical containing from 1 to 24 carbon atoms,wherein a and b can be the same or different and each have a value of 0to 6, with the proviso that the sum of a+b is 2 to 6 and n equals a+b.14. The process of claim 13 wherein said free organopolyphosphite ligandis represented by the formula: ##STR29## wherein X represents asubstituted or unsubstituted divalent hydrocarbon bridging radicalcontaining from 2 to 40 carbon atoms, each R¹ is the same or differentand represents a divalent hydrocarbon radical containing from 4 to 40carbon atoms, and each R² is the same or different and represents asubstituted or unsubstituted monovalent hydrocarbon radical containingfrom 1 to 24 carbon atoms.
 15. The process of claim 13 wherein said freeorganopolyphosphite ligand is represented by the formula: ##STR30##wherein X represents a substituted or unsubstituted divalent hydrocarbonbridging radical containing from 2 to 40 carbon atoms, R¹ is a divalenthydrocarbon radical containing from 4 to 40 carbon atoms, each R² is thesame or different and represents a substituted or unsubstitutedmonovalent hydrocarbon radical containing from 1 to 24 carbon atoms,each Ar is the same or different and represents a substituted orunsubstituted aryl radical, each y is the same or different and is avalue of 0 or 1, Q represents a divalent bridging group selected from--C(R³)₂ --, --O--, --S--, --NR⁴ --, Si(R⁵)₂ --and --CO--, wherein eachR³ is the same or different and represents hydrogen, alkyl radicalshaving from 1 to 12 carbon atoms, phenyl, tolyl, and anisyl, R⁴represents hydrogen or a methyl radical, each R⁵ is the same ordifferent and represents hydrogen or a methyl radical, and m is a valueof 0 or
 1. 16. The process of claim 1 wherein the reaction product fluidcontaining phosphorus acidic compounds is treated with an aqueous buffersolution, water, ion exchange resin or a Group 2, 11 or 12 metal oxide,hydroxide, carbonate, bicarbonate or carboxylate.
 17. The process ofclaim 16 wherein phosphorus acidic compounds present in the reactionproduct fluid are scavenged by an organic nitrogen compound that is alsopresent in said reaction product fluid and wherein at least some amountof the phosphorus acidic compound of the conversion products of thereaction between said phosphorus acidic compound and said organicnitrogen compound are also neutralized and removed by the treatment withthe aqueous buffer solution, water, ion exchange resin or a Group 2, 11or 12 metal oxide, hydroxide, carbonate, bicarbonate or carboxylate. 18.The process of claim 17 wherein the organic nitrogen compound isselected from the group consisting of diazoles, triazoles, diazines andtriazines.
 19. The process of claim 18 wherein the organic nitrogencompound is benzimidazole or benzotriazole.